How to solder batteries for a screwdriver. Proper repair of the screwdriver battery. How to repair a screwdriver battery with your own hands

A replaceable battery for a screwdriver is a rather expensive element, because its price share in the total cost of the tool reaches about 30%. Therefore, it is not at all surprising that many craftsmen are trying to extend the life of the battery in various ways. How to restore the battery of a screwdriver? - we would like to reveal such a topic in today's thematic article.

Design features of the battery for a screwdriver

Regardless of the type of power tool, brand and its specifications the structural structure of the batteries is not much different from each other. After all, when disassembled, the battery is a series circuit consisting of identical batteries.

Moreover, in most cases (for various types batteries) such cells have the same size and output voltage (V), and differ only in capacity, which is expressed in mA / h and is indicated on the cell body. In addition, when repairing a battery for a screwdriver yourself, you should pay attention to the type of elements used (Ni-Cd, Li-Ion, Ni-MH), since the recovery method for each of them may differ slightly.

It should also be noted that in order to be able to charge the elements and power the power tool, the battery design provides for power contacts (“+” and “-”) connected to the outputs of the serial circuit. Well, to protect the equipment from overheating (with forced) charge and equalize the charge level on all battery banks, two more control contacts are used through which the thermistor and resistance are connected.

We recommend that the reader read how to use an autonomous screwdriver

Battery Failure Detection Method

Considering the series connection of batteries, the primary task of the contractor will be to search for the “weak link”, because if at least one element fails, the battery will function with significant technical deviations. If we take into account that the simultaneous failure of all components of the circuit is not possible, it should be understood how to determine deviations individual elements nutrition.

Method 1. Use a multimeter

Given the identical voltage level of all components of the circuit, you can determine the faulty element using a multimeter (switching it to DCV voltage measurement mode). It should be remembered that the nominal voltages for different types of batteries have different values:

• Ni-Cd and Ni-MH (voltage 1.2V);
• Li-Ion (voltage 3.6V).

The very same method for determining a failed battery is carried out according to the following algorithm:

• The battery is set to full charge;
• The case of the device is disassembled, and alternate voltage measurements are made (using the device) on each of the cans;
• Elements are marked, the voltage on which is lower than the established norm (for Ni-Cd and Ni-MH batteries, the voltage should vary in the range of 1.2 - 1.4 V; for Li-Ion - in the range of 3.6 - 3.8 V).
• The battery is assembled and installed in a screwdriver, after which it should be discharged until a noticeable decrease in power, for which a number of power operations can be performed using a power tool.
• After discharging, the battery case is disassembled again, and again voltage measurements are taken in all sections of the circuit (special attention should be paid to marked elements)
• In the event of a voltage drop on the element of 0.5 - 0.7 V, such a battery is considered unusable.

Method 2. Use the load

The technology for detecting weak batteries in this case is similar to that described above, with the only difference being that a 12-volt light bulb (for example, 40 W) is used to discharge the battery, which will act as a load. And in order to solve the task, it will not be necessary to assemble / disassemble the battery pack several times.

After completing all the above manipulations, all unreliable elements of the battery circuit are determined, and after that a decision is made to replace or restore them.

Restoring battery cells

It should immediately be noted that it is almost impossible to restore the Li-Ion battery of a screwdriver, and all that can be done in this case is to identify weak elements and replace them.

Sometimes the problem may be hiding in the charger, which is why special attention should also be paid to the correct operation of it.

If we talk about the resuscitation of blocks, then the recovery method can be applied exclusively to Ni-Cd batteries, which are the most common for screwdrivers.

Among the main methods for the recovery of Ni-Cd batteries are the following:

• Sealing (compression);
• Elimination of the memory effect;
• Addition of boiled-off electrolyte.

How to eliminate the "memory effect"

Sometimes, the battery needs to be restored, which is associated with erasing the memory effect. Moreover, recognizing such a “disease” is quite simple: after a full charge, the battery discharges very quickly, and can again function after a short time delay. You can partially eliminate the "memory effect" as follows:

First, the battery is fully charged (if possible) with a small current, after which the battery should be completely discharged, applying a small load and thereby ensuring a slow (soft) discharge, which will allow not only the outer layer to sink, but all the plates as a whole. In this case, it is advisable to use an ordinary lamp with a voltage of 220V and a power of 60W as a load and discharge up to 30% of the rated capacity (up to about 5V).

Before using the battery, the above procedure should be repeated at least 5 times. And although the capacity of such a “reanimated” battery will be somewhat lower than a new battery, nevertheless, as a temporary measure, this technique is quite successful (it can extend the work for at least a year).

Addition of boiled off electrolyte

The most common problem with batteries for a screwdriver is the boiling of the electrolyte (especially with forced charging), which is why it is on the solution of this issue that we should dwell in more detail.

So, after determining the failed cans, you should cut the connecting plates and dismantle the required elements. After that, using a thin punch (with a diameter of not more than 1 mm), a hole should be made in the body of the can (from the minus side), through which it is necessary to add from 0.5 to 1 cubic centimeter of distilled water inside the element (having previously pumped out the same volume of air). final restoration work there will be sealing the can (you can use epoxy) and connecting the element to the existing circuit.

In the future, in order to equalize the potential of all constituent elements, using 1.5 V bulbs, you should discharge all battery banks, then perform 5-6 full charge / discharge cycles, and only after that use a power tool.

Replacing battery cans

Most effective method battery repair is the replacement of worn-out cans with new cells. Why, before restoring the screwdriver battery, you should purchase the required items, taking into account the technical and overall characteristics of the donors (they must be identical).

The very replacement of failed nodes does not cause any particular difficulties and involves the use of a soldering iron and materials for soldering (tin and alcohol flux on rosin). Moreover, in order to ensure the full operation of the battery in the process of performing work, it is advisable to adhere to the following recommendations:

• As elements for serial connection of cans, it is desirable to use existing plates, or use copper conductors with an appropriate cross section (due to high charging currents);
• To prevent jars from overheating (which can lead to breakage), soldering should be done quickly;
• The battery connection diagram must be consistent, and therefore the minus of each previous battery must be connected to the plus of the next.

The final part of the work should be the equalization of the potentials of all components that make up the battery. Why is it necessary to perform a full discharge cycle - charge the battery, and after cooling, repeat these steps at least twice.

There comes a time when a reliable home assistant - a screwdriver - stops working. Batteries are out of order, and regular recharging no longer helps. Do not rush to buy new batteries, there is another way out of the situation.

Cordless screwdriver - what power sources are used?

The cost of batteries is about 70% of the price of a new tool, so it is logical to try to repair the battery of a screwdriver. Before proceeding with the operation, you should familiarize yourself with the features of the voltage sources, find out what type of battery is used on your tool. Their structure is absolutely the same and does not depend on the country of manufacture and brand. Inside the plastic box are serially connected elements of a standard size. On each element there is an indication of the type and capacity in ampere-hours (A / h).

Screwdriver battery

Batteries are equipped with elements of the following types:

• lithium-ion (Li-Ion) - with an element voltage of 3.6 V;
• nickel-cadmium (Ni-Cd) - 1.25 V per element;
• nickel-metal hydride (Ni-Mh) - 1.2 V.

Evaluating lithium-ion power supplies in terms of quality and service life sets them apart from the competition. They practically do not lend themselves to self-discharge, high capacity, they can be recharged many times, several times more than other types of batteries. The cell voltage is three times higher than that of other types, which allows batteries to be equipped with fewer cans, reducing weight and dimensions. They do not have a memory effect, which makes them an ideal device of this kind.

But there is no ideal in nature, and lithium-ion power sources also have some drawbacks. They cannot be used at sub-zero temperatures, as manufacturers honestly say. But practical use revealed another drawback: when the operational life of such a battery ends (three years), lithium decomposes, no means of making a reverse reaction bring results. The price of such batteries is three times higher than other power sources for a screwdriver.

Nickel-cadmium batteries are the most common due to their low cost. They are not afraid of negative temperatures, like lithium-ion voltage sources. If a screwdriver is rarely used, such elements are ideal, because they can be stored discharged for a long time, while maintaining their characteristics. Such batteries have a lot of disadvantages: they are of small capacity, toxic, so their production is concentrated in underdeveloped countries. The tendency to self-discharge, short life expectancy with intensive use - also belong to the disadvantages of these batteries.

Nickel-cadmium batteries dry out at the end of their useful life. Those who know about this feature refill them, but this operation is not easy to perform, so few decide on such an action, preferring to replace individual battery banks. If the cause of failure is the memory effect, which is considered a big disadvantage of nickel-cadmium batteries, it is possible to restore their performance by flashing.

Nickel-metal hydride batteries are environmentally friendly, high quality, produced by the world's leading companies. Compared to Ni-Cd, they have clear advantages:

• slow self-discharge;
• the memory effect is small;
• resistant to multiple discharge-charge cycles;
• relatively large capacity.

But during long-term storage without work, some of the characteristics are lost, they do not like low temperatures, and besides, they cost a lot. And the main disadvantage is that they cannot be repaired.

We determine the malfunction - is it repairable?

If you have elements installed on the screwdriver in the battery that, in principle, can be repaired (except for nickel-metal hydride), we proceed to disassemble the case. It has two parts connected with screws or glue. In the first case, no difficulties are foreseen - we unscrew the screws and separate the parts. If the connection is glued, we insert a knife between the parts at the junction, then we screw a self-tapping screw into this place. Carefully, so as not to damage the elements, we pass the knife along the joint, separating the parts of the case.

We check the elements on a fully charged battery.

Having disassembled the case, we will see banks connected in series, which means that a malfunction of even one bank can lead to poor battery performance. The main task during the repair is to find weakness in the chain. We remove the cells from the body and lay them out on the table so that there is convenient access to all contacts. With a multimeter, we measure the voltage of each element, write down the indicators on paper or directly on the case. The voltage indicator on a nickel-cadmium battery should be 1.2-1.4 V, on a lithium-ion battery - 3.6-3.8 V.

Types of malfunctions and methods for their elimination

Having measured the voltage, we assemble the cans into the case, turn on the screwdriver and work until it loses power. Again, we disassemble and re-take the voltage indicators, again we fix. Cells with the lowest voltage after being fully charged will again show a significant drop in voltage. A difference of 0.5–0.7 V is considered significant. Such elements will soon become completely unusable, they are candidates for resuscitation or complete amputation.

If you have a 12-volt tool, you can use a simpler method for troubleshooting, eliminating the double disassembly-assembly. First, we also measure the voltage of each fully charged element, fix the indicators. We connect the load to the banks laid out on the table - a 12 V light bulb, which will discharge the battery. Next, we are again interested in voltage. Where there is the strongest drop - a weak area.

Changing elements is the most reliable way

You will either need cans from an old battery, in which serviceable elements remain, or you will have to buy new ones, they are inexpensive. When buying, pay attention to the dimensions and capacity - they must match the existing elements. We throw out the bad cans, solder new ones in their place. It is desirable to connect using native plates or copper ones that are suitable in size. Compliance with the cross section is important - when charging, a large current passes through the contacts. If the area is insufficient, they heat up, the protection works.

We pay special attention to the connection sequence - the minus of one can is connected to the plus of the other.

On the assembled battery, we equalize the potentials, since they are different. We put it on charge for the whole night, let the battery rest for a day, then measure the voltage. Ideally, all elements should have the same indicator. We turn to the discharge of the battery until it is completely depleted. We repeat the procedure twice more. It should be said that such training is necessary not only for repairs, it should be carried out every three months in order to extend the life of the battery.

Restoring capacity - flashing batteries

A method acceptable for nickel-cadmium batteries when the cells are not dry. You can verify this using the method below, if it does not help, then the electrolyte has boiled away. The essence of the method is in charging using high current and voltage. It will take Charger with the possibility of regulation, charging for car batteries is suitable. We will charge each element separately, for which we remove the battery from the case and disconnect the banks from one another.

We set the charging voltage to three times the nominal voltage - 3.6 V. We connect it to the charger and turn it on for 3-5 seconds. If the voltage test with a multimeter showed 1.4 V or a little lower, everything is in order. We collect the battery and use it. The method relieves batteries from the memory effect. It is not suitable for completely dead cans.

Battery resuscitation - proven in practice

As already noted, the main reason for the failure of nickel-cadmium batteries is the drying of the cans. The procedure for topping them up is not very pleasant, but not so complicated that it cannot be performed. We do everything, as always - we disassemble the case, take out the elements. We remove the paper with which the banks are wrapped. From some it is removed easily, whole, on some it has to be cut. We examine the body of the cells - some without any signs of corrosion, others can be seriously damaged, but the main thing is that the shell is intact.

With a thin drill at the top of the element, where there is a recess in a circle, we make a hole. You will need distilled water. We draw it into a syringe, insert the needle into the hole and pump water very slowly. It is not known how much it will enter, it is impossible to determine visually. If liquid flows from the can from the very beginning of water input, throw it away, it cannot be resuscitated, it is necessary to replace it with a new element. Some kind of reaction occurs there, which indicates the unsuitability of this element for repair. But this happens very rarely. Further procedures are usual - assembly, several charge-discharge cycles.

Lithium-ion batteries can also be recycled, but this operation is unhealthy due to the toxicity of the contents. The reason for their failure is most often a violation of the contact between the internal filling and the exit to the case. To check the suitability for repair, insert an awl into the hole at the top of the element so that it touches the inside. We connect a multimeter and look at the readings. If there is current, the reason is a broken contact, you can continue the repair.

With wire cutters we cut off a part of the metal on the cover protruding from the top of the element. We bend it upwards, and opposite the body metal we press it so that it touches the inside of the element. Now comes the turn of the most critical part of the operation - soldering. We use solder that has a flux inside, it is faster and more convenient to solder with it, especially in such a situation. We solder quickly so as not to overheat the element. If you don’t know how to do this, don’t take it - in this situation you won’t learn, but ruin everything. Then we close the gap in the case with sealant - and for charging.

It's real if you use one of the above methods!

And needs to be replaced. Buying a new one is often not easy, and if it is possible, then at a very high price. Therefore, they say that it is easier to buy a new tool, or to repair the battery of a screwdriver yourself.

There are a large number of videos on the Internet in which electronics lovers clearly show how to repair a screwdriver battery with their own hands. If you are seriously puzzled by the question, think about saving Money and whether it is possible to fix the battery of a screwdriver with your own hands, watching such videos can be a good start in order to repair the battery yourself in the future.

How to disassemble the battery

Battery packs of home tools almost do not differ from each other in their design, regardless of the model of the tool (Bosch, Makita, Hitachi). They are packaged in a plastic case consisting of two parts. The number of batteries may vary depending on the output voltage of the tool being used. All elements are soldered in a certain sequence. Lead ends or terminals, where battery voltage measurements are usually made, are brought out.

Most battery packs of a screwdriver or drill are designed so that they are very easy to disassemble, regardless of whether we are repairing the battery of an Interskol screwdriver or another model. A few fixing screws need to be unscrewed with a regular screwdriver. There are batteries that are difficult to disassemble, but lend themselves to a screwdriver and a penknife. The adhesive layer is removed with a knife, and two mating surfaces are moved apart with a sharp self-tapping screw.

The difference between the batteries of screwdrivers from each other may be the presence or absence of a temperature sensor that automatically turns off the battery under conditions of critical heating (above 50 ° C). The sensor constantly monitors the temperature not only under load, but also in the conditions of the current battery charge. The controller reads all the data and processes them, "remembers" the capacity and other indicators. As soon as the capacity reaches 80-90%, and the voltage is 14 V, the control unit turns everything off. Such batteries serve for years without losing their technical characteristics.

The market offers a large number of inexpensive models of screwdrivers.
Cheaper devices do not have these technical devices, and all processes must be monitored independently.

Types of battery repair

How to reanimate the battery of a screwdriver? Three ways can be distinguished:

• express battery repair by zapping method ;
• replacement of individual cells in the battery ;
• replacement of all elements of the battery pack .

Express repair of nickel-cadmium batteries using the zapping method

Translated from English, this means burning through, applying short pulses of high current for several seconds. We can say that this is a kind of emergency resuscitation of batteries. It should be noted right away that this option is quite risky, and not every battery is able to withstand such “shock therapy” with high current. The use of high current is only possible if nickel-cadmium batteries are installed in the screwdriver. Other batteries ( , ) must not be subjected to such an impact.

The essence of the purge is to destroy the crystals formed inside the nickel-cadmium batteries with a high current. These crystals are called dendrites, and because of their growth, the capacity of the battery gradually decreases. "Pumping" with high currents quickly destroys the formed crystals and sharply reduces the self-discharge of the battery.

It is claimed that zapping can be effective for any NiCd, even if they are completely discharged to zero or have been lying without use for 10 or 20 years. The question is always the likelihood of a successful repair in such "hard" cases - when the batteries are "repaired" in this way, it will either succeed or not. However, it doesn't hurt to try to revive them. Of course, with the utmost care.

For Zapping you will need:

• any high current charger ;
• multimeter to monitor voltage ;
• welding machine ;
• crocodile clip ;
• zapping electrode ;
• protective equipment .

As a charger, you should not use an ordinary power supply. Even if the current strength of such chargers is 10-15 A, they will not withstand strong voltage. With a double-sided clamp on one terminal, a tight contact is ensured, and the electrode itself will be held on the other terminal. It is impossible to hold it with your fingers: during burning, it will become hot. A zapping electrode is a piece of wire that is wrapped in a tight bundle (no insulation). Its cross section is a maximum of 1.5 mm 2, and its length is 6-7 cm.

Instead of higher quality welding machine especially daring electronics lovers repair batteries using an ordinary soldering iron. But a spot soldering tool would be preferable for repairs. Protective equipment (gown, goggles, special non-flammable substrate) is necessary because sparks always appear during high current purging.

Work progress

It is better to blow each battery separately, the algorithm of actions is as follows:

• Fix the electrode with the minus sign on its minus pole. Do not confuse the polarity, an important point.
• "Purge" the positive electrode with short pokes, their frequency is 2-3 times per second . Usually, for a can with an output voltage of 1.2 V, blowing must be done for 3-4 seconds at a frequency of 2-3 small pokes per second;
• Measure the voltage readings after the first stage . It should be raised to a maximum of 1.3 V. If the voltage is higher, reduce the time of pokes or their number.

You need to poke very quickly and carefully, not allowing the electrode to weld even for a short time to the pole of the Ni Cd battery of the screwdriver, in order to avoid complete burning of the battery. It is recommended to put on a protective intermediate electrode on the positive electrode, or hook a "crocodile" to protect the surface of the battery pole.

The procedure is repeated up to 25 times - until the battery capacity is restored. During the whole process it is necessary to constantly monitor the temperature of the batteries. The intervals between zappings must be at least 15 minutes. Only in this case, the reanimated battery will have a chance to extend its service life.

Replacement of individual cells in the battery

If the battery capacity drops, it means that at least a few of its cells are out of order. All batteries cannot “sit down” at once, so first you need to find the smallest batteries in the chain, and then disassemble the battery and replace them with new ones.

New batteries can be ordered from any online store. At the same time, it is important to buy those elements whose type and capacity are fully consistent with the previous ones. If there are nickel-cadmium batteries in the screwdriver, then it is worth buying the same ones with the same level of capacity. If you manage to get the same battery, you can remove the most capacious elements from it and put it in the one that is being repaired.

How to identify "weak links"

There are two ways to search for dead batteries in a circuit:

• using a multimeter ;
.

For the first method, you only need a multimeter:

• charge the battery fully ;
• disassemble the battery case ;
• measure the nominal U on each battery (nominal for nickel-cadmium batteries - 1.2 V, for lithium-ion - 3.6 V);
• mark with a cross the elements on which U is lower than the nominal not to be confused with others;
• assemble the battery ;
• turn on the screwdriver ;
• work until a noticeable decrease in power ;
• disassemble the battery again, measure U again .

On batteries that are marked with a cross, the "dips" in voltage will be much larger than the rest - most often, below 1 V. As for the difference between the U values ​​​​in the battery, then if it is at least 0.5-0.7 V, this is very significant.

The second way to find "dead" batteries is less laborious and simpler. If the output voltage of the screwdriver is 12 V, you will need a lamp with the same output voltage.

Course of action:

• charge the battery fully ;
• connect the lamp as a load to both poles of the battery ;
• wait until the battery is fully discharged ;
• measure the voltage indicators at the terminals of all elements in turn with a multimeter .

"Dead" batteries are easy to separate because their voltage drops the most after discharging.

Repair

So, the elements that failed were found, new ones were purchased, and now you can proceed directly to the repair of the battery.

To repair the battery, you will need:

• soldering iron;
• low corrosivity flux ;
• tin;
• copper plates (in case the "relatives" broke during parsing) .

Spot welding in case partial renovation The battery is optional. But during soldering, you need to carefully monitor so as not to overheat the elements. It is best to connect the batteries to each other using the plates that they had. If they break during the disassembly of the battery into individual elements, then new copper plates will need to be made.

Do not forget about polarity. Each battery element for a screwdriver is connected to its neighbor according to the principle of a certain sequence. The minus of one can must be connected to the plus of the other, and the minus of the other can must be connected to the plus of the third, and so on.

After the chain is reassembled, care must be taken to ensure that the voltage potential of all elements is equal. To do this, you should leave the batteries on charge for the whole night, then they should cool down over the next day. After that, the voltage is measured on each element. If the soldering and the charge cycle were carried out correctly, then the multimeter will show approximately the same U number - 1.3 V on all batteries.

Now you need to carry out at least two charge-discharge cycles for the battery in a natural way: place the repaired battery in your own screwdriver and work it until it is completely discharged.

By the way: partial repair of a Li-ion battery of a screwdriver can be carried out in a way that requires minimal financial costs. If 18650 batteries are installed in the block, it is really possible to borrow the same ones from an old non-working laptop, if possible.

Replacing all elements of the battery pack

The required number of cells can be ordered at any online store, depending on the number of old batteries. It is important to pay attention to the fact that all of them initially had the same capacity.

You can completely replace all the elements of the battery pack with new nickel-cadmium batteries. They cost much less than nickel-metal hydride batteries and, compared to other batteries, are the most durable and hardy. However, recently, independent conversion of batteries “from cadmium to lithium” has been increasingly practiced, in other words, installing new lithium-ion batteries instead of old Ni-Cd.

Despite their reliability, nickel-cadmium batteries can fail quickly because they are connected in series to each other without a balancing board. If the batteries are of the same batch of manufacture, their parameters will still have a large spread among themselves. With this connection, one element will charge faster, the other slower, and the third may be recharged.

To produce a complete from nickel-cadmium to lithium-ion, you will need:

• number of elements equal to the number of previous (with the same capacity indicator);
• 5S balance board (its amperage depends on how many volts the screwdriver is designed for);
• tester or multimeter ;
• soldering iron with a good "sting" ;
• quality flux and lead solder ;
• silicone wires AVG 16 ;
• heat resistant tape and hot glue .

Discharge batteries before soldering. Remove the old batteries from the block and release the contacts. It is better not to throw away the old temperature sensor, but leave it as an additional protection against lithium overheating.

Now the main thing is to properly solder the lithium . Pre-cut the wires to the desired length, insulated, in silicone, very thick to avoid melting when the lithium is heated. The battery pads for soldering are cleaned with a knife.

It is good to heat up the soldering iron, up to 300 ° C, and start soldering with the help of flux and lead solder. The flux must be of good quality, indelible, non-conductive. Never use acid fluxes. Soldering should be no more than 2 seconds to avoid overheating of lithium. In order for the heat to escape faster, after soldering, you can attach any iron object to the battery that takes heat away.

Let the batteries cool down and connect the "pluses" to the "minuses" as usual. Check overall voltage. Its indicator should be on average 20.7 V if there are 15 elements.

After measuring the voltage, the board is connected. All its wiring must be laid with special gaskets so that nothing “shorts” during operation. The entire battery pack is held together with heat-resistant tape designed specifically for insulating batteries and their contacts.

Solder wires and connector. If the contacts "dangle", they can be put on hot melt adhesive. Now, finally, you can finally assemble the battery pack of the screwdriver and check its operation.

Sometimes it seems that it is very difficult to repair the battery of a Hitachi screwdriver (or other tool). But if you understand general principles, such as the basics of electronics, from the inside, and the main principles of proper soldering, it becomes clear how to repair the battery for a screwdriver yourself. This will not only save financial resources but will also contribute to the acquisition of valuable and useful skills.

A process such as restoring a screwdriver battery requires a certain amount of knowledge. How to resuscitate this tool, how not to make a mistake and not ruin the battery and the screwdriver as a whole - many people ask such questions. Let's consider them.

The screwdriver is a special hand tool, which is used for tightening and unscrewing bolts, screws, nuts, self-tapping screws and screws. Also, a similar device is used for high-quality and fast drilling of holes and for the threading process. For modern craftsmen, the tool replaces a conventional screwdriver, only saving a lot of time.

The tool is simply indispensable in a variety of construction processes, V repair work Oh. If you need to assemble furniture, you can not do without a screwdriver. Every master who has worked with a screwdriver for a long time, after using a screwdriver, understands how much more time is saved. The versatility of the tool and its functionality is becoming more and more.

The modern market offers a wide variety of models, but regardless of the brand, batteries have an identical structure. If you disassemble the battery, you can see that it is assembled from relatively small structural elements, assembled strictly sequentially.

The special typesetting parts present in the composition have standard sizes and voltage level. Only the capacity, which is measured in A / h, can differ, and is indicated strictly on the element itself.

The case has four contacts. Among them, the presence of the following can be noted:

Two power, for discharge and charge;
Upper control, which is connected through a special thermal sensor. Such a device is necessary for effective protection batteries, it also turns off and in a special way limits the charge current by raising the temperature to certain indicators. The heating process is carried out due to sufficiently large currents during the forced charge, that is, a special “fast” charge is carried out;
It can be noted that there is a so-called "service" contact, which is connected through a special resistance. It is used for fairly complex charging stations, which are designed to equalize the charge of all battery cells without exception. It is worth noting that such stations are not needed in everyday life, since there is a high cost.

During operation, the tool may fail. When such a situation arises, it is required to be able to determine the malfunction. At the same time, all the elements present cannot fail, since their circuit is strictly sequential. When one part fails, the entire circuit fails. It is for this reason that it is important to identify the weakest point.

Approximately 70% of the total cost of a brand new screwdriver falls on the battery that usually comes with it.

Usually the battery of this tool fails after a certain period of use. In such a situation, you will have to purchase a completely new battery or have it quality repair screwdriver, saving a significant amount of material resources.

What repair tools are needed

To repair the battery of a screwdriver with your own hands, you should have the following tools with you:

Ammeter 2 A;
tester;
voltmeter for 2 and 15 V;
ohmmeter;
milliammeter;
screwdriver to open the case;
magnifier;
scissors;
pliers.

The repair of such a tool for the most part consists in finding and then replacing a failed battery cell. To achieve this goal, it is important to know the order, the sequence of the verification, and it will also be necessary to analyze the parameters.

Features of repair technology

Often, during the repair process, it is required to apply technologies for the complete restoration of terminals and for the restoration of capacitance. Often a breakdown is indicated by the fact that the battery of the screwdriver does not charge. There are many reasons for this:

Malfunction of the supplied charger;
The cause may be a strong deterioration of the battery;
There is a violation of strong contact between the installed terminals.

If signs of damage appear, the battery must be repaired immediately. The exact cause of a battery failure can be determined by measuring the voltage level with a special tester. Similarly, every battery needs to be tested. All faulty batteries found during the test must be labeled and separated from those that are working properly.

If the battery is draining quickly, before you immediately disassemble it and change anything in it, first try to restore the battery capacity by several cycles of deep discharge and full charge. In 7 out of 10 cases, this helps restore battery capacity.

Often the cause of the breakdown is a malfunction of the terminals. During the use of the device, they unbend, which entails poor contact, respectively, the battery will be charged every other time. To carry out repairs, you first need to disassemble the charger, carefully bend all the terminals, and then simply control the charging process using special devices.

If during the operation of this device its capacity is lost, and a series of successive charges-discharges did not help, then it is worth replacing this important element for operation.

Below are the videos, it’s better to see once what to do with a broken battery than to listen or read, the first one shows the disassembly of the battery case, the second video already shows the battery recovery process itself.

Capacity recovery method

Often the battery of the battery is in need of restoring its capacity. This volume is usually lost due to the erasure of the memory effect. Determining this problem is quite simple. Once the battery is fully charged, it usually discharges very quickly and only starts functioning again after a certain time delay. Fixing this kind of problem is pretty easy. It is enough to follow the following instructions:

1. A small current is required to fully charge the battery.
2. After that, completely discharge it, using a small degree of load. In this way, a slow, i.e. relatively soft, discharge can be ensured, which will allow the outer layer and the entire plate to sag.
3. For a load of such a plan, it is better to use a standard lamp, the voltage of which is 220 V and the power parameters are 60 V.
4. The discharge is required to produce up to about 30% of the total rated capacity, that is, up to 5 V.

Before using the screwdriver battery, it is advisable to repeat this procedure up to 5 times. Although the capacity of a refurbished device will be slightly lower than a new one as a temporary measure, this method is quite successful. Such manipulations are able to extend the operating time of a screwdriver by about a year.

And in this video there are already bulkheads of batteries, how to make one worker out of 2.

Various alternative solutions to the problem

There are a few alternatives complete battery recovery. Among them, the following methods are very popular:

1. Gentle compression and slight deformation of the case. In other words, you can do as you previously did with the battery, that is, a little by means of light strokes, compress.
2. The following process can be carried out - the batteries are strongly charged with a stronger current. After that, they are completely discharged and charged again. Usually, such shock therapy gives a fairly good result, that is, it is able to restore batteries that previously seemed hopeless to life.

If through the application of certain mechanical influences, operability cannot be restored, it will need to be replaced.

The nuances of self-repair

Do-it-yourself battery repair of a tool such as a screwdriver can be done by replacing all the faulty parts present. In the process of acquiring a new element, it is necessary to carefully ensure that the dimensions and capacity are fully consistent with all native components. If a defective component is found, it will need to be cut off, and then soldered in its place with a new one.

Speaking of important points and the nuances of this process, the following factors can be noted:

When using a soldering iron, you need to work quickly so that the battery does not heat up;
The connection process must be carried out using plates;
It is worth constantly remembering that the connection of all elements is carried out strictly sequentially.

After major repairs, the potentials on the batteries can be completely different. Therefore, they need to be aligned. For this purpose, you will need to charge the battery for 12 hours, then let it cool for a day. A device for measuring the voltage present must show the same parameters of 1.3 V on all components without exception. It is recommended to do this several times.

Carrying out the restoration of a screwdriver with your own hands will save material resources in the workshop and without the need to purchase a new tool. To achieve the ideal quality result just follow the rules and instructions above.

This video shows the disassembly of the battery

Today, almost every good owner has in his "armament" in the pantry or in the garage a universal tool for assembling furniture, repairing a car and other equipment - a screwdriver. Unlike a power tool with a traditional power cord, it is equipped with a powerful battery and does not require an electrical connection. Often the cost of a new battery can be up to 70% of the entire device and, at times, many people think about the advisability of purchasing a new battery. An excellent way out of this situation is to repair the battery of a screwdriver with your own hands, which will help to significantly reduce costs.

Regardless of the manufacturer and model, the battery of a screwdriver is a plastic case in which several batteries are placed.

Connected battery banks of a screwdriver

The number of cans in the shell can vary from a few to a dozen pieces. Connected in series, the terminals of the first and last battery are closed, while providing a connection to the charger. The supply voltage in household appliances ranges from 9 to 18V. In some professional devices, the EMF value can reach up to 36V, which will certainly affect the battery life.

In addition to cans, the battery case may contain a temperature sensor and a thermal interrupter that serve to open the circuit in case of possible overheating of the device. Any rechargeable lithium-ion (Li-Ion) screwdriver battery is equipped with a special controller that ensures optimal discharge and battery operation under load.

Types of screwdriver batteries

Currently, the most popular and sought-after manufacturers of screwdrivers are the following types:

Nickel-cadmium batteries (NiCd).

Nickel-cadmium battery screwdriver

The cathode of this element is nickel hydrate with graphite powder and electrolyte. Cadmium oxide hydrate Cd (OH) 2 acts as an anode. The electromotive force (EMF) of the battery is about 1.37V. Depending on the quality of the materials used and the production technology, the service life of a nickel-cadmium screwdriver battery is about 15-25 years with an average number of charge-discharge cycles of 600 times.

To the benefits NiCd - batteries can be attributed to:

- durability. With proper operation, the period of normal operation of the battery can be 25 years;

- operation with no high temperatures Oh. Thanks to their chemical properties the charge of a battery of this kind practically does not change with decreasing temperature, which makes it possible to use it in the harsh climate of our country;

- unpretentiousness in work;

— the possibility of storage in a state of discharge. Unlike other types of batteries, nickel-cadmium screwdriver batteries can be stored for a long time in a discharged state without deteriorating their properties;

- a large number of charge-discharge cycles.

The disadvantages of nickel-cadmium batteries are:

- memory effect. In case of incomplete discharge, the battery element can “remember” the minimum charge level and, upon subsequent connection to the charger, will be filled with energy only up to this level;

- high specific gravity. With the same dimensions, the mass of the battery based on nickel hydrate and cadmium oxide will be significantly larger;

- Disposal problems. The high toxicity of the filling often causes disposal problems.

Nickel metal hydride batteries (NiMH).

Nickel-metal hydride screwdriver can

Are prominent representatives alkaline batteries are included in the group of chemical type power supplies. The cathode is nickel oxide (NiO), and the anode is a hydrogen metal hydride electrode. The initial EMF of this kind of battery is 8.4V, but over time it drops to 7.2V. Compared to nickel-cadmium, NiMH batteries have 20% more capacity with an average of 250 charge-discharge cycles.

Advantages of NiMH power supplies:

- high capacity with relatively small weight and dimensions;

- no memory effect. It is possible not to fully charge the battery, and with subsequent connections to the charger, the maximum capacity will be restored in the battery with full discharge during operation;

- environmental Safety. Fillers nickel-metal hydride batteries of a screwdriver are not dangerous for the environment and humans, and therefore do not require special disposal;

- resistance to damage. With strong impacts, NiMH battery banks are not destroyed and are able to work in the same mode.

Disadvantages of nickel-metal hydride batteries:

- high level of self-discharge. When stored for a long time, the battery is strongly discharged and requires connection to the charger. To prolong the life of the battery, it is necessary to fully discharge and re-charge it;

- a small number of charge cycles. Unlike nickel-cadmium batteries, the number of charge-discharge cycles for nickel-metal hydride batteries is only 250-500 times;

- intolerance to high temperatures. When the thermometer rises to 25 degrees Celsius, the battery loses its properties over time.

Lithium-ion batteries (Li-ion).

Lithium-ion screwdriver power supply

Batteries of this type are widely used in consumer electronics and energy storage systems and are a cathode separated by a porous separator on aluminum and an anode on copper foil. The charge carrier in such a battery is a charged lithium ion, capable of being introduced into the crystal lattice of other materials (oxides, graphite, etc.). The nominal voltage is 3.7V, and the maximum is about 4.3V. With a gradual discharge, the EMF drops to 2.5-3.0 Volts, depending on the capacity of a particular screwdriver battery model.

Advantages of Lithium Ion Screwdriver Batteries:

- the possibility of recharging at almost any stage of discharge without negative consequences in the future;

- the complete absence of the "memory effect" inherent in nickel-cadmium batteries;

— absence of unsafe chemical elements;

– long service life (6-8 years);

- high charge power with relatively small dimensions;

- High speed full charge.

Disadvantages of lithium-ion batteries ( Li- ion):

- high cost;

— self-discharge at low temperatures;

- sensitivity to mechanical damage (shocks);

- intolerance to overcharging when fully charged.

Do-it-yourself battery repair for a screwdriver

When problems occur in the power system, it is first necessary to determine the cause of their occurrence. Almost all malfunctions associated with the repair of a screwdriver battery can be fixed independently. This does not require the use of a specialized tool and a set of locksmith screwdrivers and a soldering iron is enough.

Battery troubleshooting

Having identified faulty battery power sources, you need to choose one of the ways to restore its performance. In the first case, it is enough to add distilled water to defective jars in case of electrolyte evaporation and charge them with a current with more high voltage different from nominal. The second way is to completely replace individual elements with new ones. Many experts recommend using the second way to solve the problem, since there is no guarantee that the restoration of the properties of the jar will give the desired results.

In practice, it has been proven that it is possible to restore a defective battery bank only in power sources with a "memory effect", which are nickel-metal hydride and nickel-cadmium cells. For these purposes, you will need a professional charger with the ability to adjust the current and voltage parameters. We set a voltage of about 4 volts with a current of 200 mA on the memory panel and act exclusively on defective banks identified during battery diagnostics.

Filling a battery can with distilled water

You can restore the screwdriver battery by making a small hole in the shell and adding distilled water to the electrolyte. To do this, we take a thin drill up to 1.5 mm and pump out 1 cubic centimeter of electrolyte with a medical syringe. We add the same amount of water to the vacated space and seal the hole with a sealant or epoxy resin. After connecting the cans to one circuit and assembling the case, we perform the charging and discharging procedure 5-6 times in order to form the so-called “memory” in the power source.

Replacing defective battery cans of a screwdriver

Connecting a new screwdriver battery

To do this, it is necessary to disconnect the defective jar from the common plate using ordinary side cutters and solder a new battery in its place. It is worth noting that when cutting off the old can, it is necessary to leave a sufficient end of the contact for the possibility of soldering a new element. After assembling all the cans, it is necessary to repeat the charge / discharge cycle several times in order to equalize the voltage in each element (about 1.3V). When performing the soldering procedure, it is important not to overheat the element, as this may affect its further performance.

Repair of a lithium-ion battery of a screwdriver is carried out in the same way, with the exception of disconnecting / connecting the control board.

Do-it-yourself screwdriver battery repair was last modified: June 5th, 2019 by Administrator