How to properly solder batteries for a screwdriver. Correct 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 using various methods. How to restore a screwdriver battery? - this is a topic we would like to reveal in today's thematic article.

Design features of the battery for the screwdriver

Regardless of the type of power tool, brand and its technical characteristics the constructive structure of the batteries is not much different from each other. Indeed, the disassembled battery is a sequential circuit consisting of identical batteries.

Moreover, in most cases (for different types batteries), such cells have the same size and output voltage (V), but differ only in capacity, which is expressed in mA / h and is indicated on the cell body. In addition, when self-repairing a battery for a screwdriver, 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 be slightly different.

It should also be noted that for the possibility of charging the cells and powering the power tool, power contacts ("+" and "-") are provided in the battery design, connected to the terminals of the serial circuit. Well, to protect the equipment from overheating (with forced) charging 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 about how to use an autonomous screwdriver

Battery Malfunction Detection Method

Taking into account the serial connection of the batteries, the primary task of the contractor will be to find the “weak link”, because if at least one cell fails, the battery will function with significant technical deviations. If we consider 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. Using 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 the 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 of determining a failed battery is made according to the following algorithm:

• The battery is set to full charge;
• The body of the device is disassembled, and alternate voltage measurements (using the device) are made on each of the cans;
• Cells are marked, the voltage on which is below 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 - within 3.6 - 3.8 V).
• The battery is collected and installed in a screwdriver, after which it should be discharged to 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 the voltage is measured again in all sections of the circuit (special attention should be paid to the marked elements)
• In the event of a voltage drop across the cell of 0.5 - 0.7 V, such a battery is considered unusable.

Method 2. Using a load

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

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

Battery cell recovery

It should be noted right away 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 hidden in the charger, therefore, special attention should be paid to its correct operation.

If we talk about the resuscitation of the 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 recovering Ni-Cd batteries are the following:

• Compaction (compression);
• Elimination of memory effect;
• Adding the boiled down electrolyte.

How to eliminate the "memory effect"

Sometimes, the battery needs restoration, which is associated with the erasure of the memory effect. Moreover, it is quite simple to recognize such a "disease": after a full charge, the battery discharges very quickly, and can function again after a short time delay. You can partially eliminate the "memory effect" as follows:

At first, the battery is fully charged (if possible) with a small current, after which the battery should be completely discharged using a small load and thereby providing a slow (soft) discharge, which will allow not only the outer layer to sink, but all the plates entirely. 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 nominal 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 slightly lower than the new battery, nevertheless, as a temporary measure, such a technique is quite successful (it can extend the operation for at least a year).

Adding boiled out electrolyte

The most common problem with rechargeable batteries for a screwdriver is the boiling off of electrolyte (especially with a forced charge), which is why it is necessary to dwell on the solution of this issue in more detail.

So, after identifying the failed cans, cut the connecting plates and dismantle the required elements. Then, using a thin punch (no more than 1 mm in diameter), a hole should be made in the can body (from the minus side) through which 0.5 to 1 cubic centimeters of distilled water must be added to the inside of the element (after pumping out a similar volume of air). The final restoration work there will be a sealing of the can (you can use epoxy resin) 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 light bulbs, all the battery banks should be discharged, then perform 5-6 full charge / discharge cycles, and only then use the power tool.

Replacing battery cans

The most effective method of battery repair is to replace worn-out cans with new elements. Why, before restoring the screwdriver battery, you should acquire the required items, taking into account the technical and dimensional characteristics of the donors (must be identical).

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

• It is advisable to use existing plates as elements for serial connection of cans, or use copper conductors with an appropriate cross-section (associated with high charging currents);
• To prevent overheating of cans (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 one.

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

There comes a time when the reliable home helper - the screwdriver - stops working. The batteries are out of order, and regular recharging no longer helps. Do not rush to buy new batteries, there may be 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 voltage sources, find out what type of batteries is used on your instrument. Their structure is absolutely the same and does not depend on the country of production and brand. Inside the plastic box there are standard-sized daisy-chained elements. Each element has an indication of the type and capacity in ampere-hours (A / h).

Screwdriver battery

Batteries are completed with the following types of elements:

• lithium-ion (Li-Ion) - with a cell voltage of 3.6 V;
• nickel-cadmium (Ni-Cd) - 1.25 V on each cell;
• nickel metal hydride (Ni-Mh) - 1.2 V.

Assessment of lithium-ion power supplies in terms of quality and service life puts them out of competition. They practically do not lend themselves to self-discharge, high capacity, they can be charged repeatedly, several times more than other types of batteries. The cell voltage is three times higher than that of other types, which makes it possible to equip batteries with fewer cans, reducing weight and dimensions. They have no memory effect, which makes them an ideal device of this kind.

But the ideal does not exist in nature, and lithium-ion power supplies also have some disadvantages. They cannot be used at subzero temperatures, as manufacturers honestly declare. But practical use revealed another drawback: when the service life of such a battery ends (three years), lithium decomposes, no way to do a reverse reaction brings results. The price of such batteries is three times higher than that of other power sources for a screwdriver.

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

Nickel-cadmium batteries dry up at the end of the shelf life. Those who know about this feature re-fill them, but this operation is not easy to perform, so few decide on such an action, preferring to replace individual battery banks. If the reason for the 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, moreover, they cost a lot. And the main drawback is that they cannot be repaired.

Determining the malfunction - can it be repaired?

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

We check the cells on a fully charged battery.

Having disassembled the case, we will see cans connected in series, which means that a malfunction of even one 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 case and lay them out on the table so that there is convenient access to all contacts. We measure the voltage of each element with a multimeter, record the indicators on paper or directly on the case. The voltage indicator for a nickel-cadmium battery should be 1.2-1.4 V, for a lithium-ion battery - 3.6-3.8 V.

Types of malfunctions and how to fix them

Having measured the voltage, we collect the cans in the case, turn on the screwdriver and work until it loses power. We again disassemble and re-remove the voltage indicators, again fix it. Cells with the lowest voltage will again show a significant drop when fully charged. The difference in readings 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, a simpler method can be used to troubleshoot the problem by eliminating double disassembly and assembly. First, we also measure the voltage value 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 the strongest fall is noted - the weak area.

Changing elements - the most reliable way

You will need either cans from an old battery, in which there are serviceable elements, or you will have to buy new ones, they are inexpensive. When buying, we pay attention to the size and capacity - they must match the existing elements. We throw out the unusable banks, and in their place we solder new ones. It is desirable to connect using native plates or copper plates of suitable 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, protection is triggered.

We pay special attention to the sequence of the connection - the minus of one can is combined with 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 proceed to discharge the battery until it is completely depleted. We repeat the procedure twice more. It should be said that this training is necessary not only for repairs, it should be done every three months to extend the life of the battery.

Capacity recovery - battery flashing

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 charging using high current and voltage. It will take charger adjustable, suitable for charging car batteries... We will charge each element separately, for which we remove the battery from the case and disconnect the banks from one another.

We set up the charging for a voltage three times higher than the nominal - 3.6 V. Connect to the charger and turn on for 3-5 seconds. If the voltage test with a multimeter showed 1.4 V or slightly lower, everything is in order. We collect the battery and use it. The method eliminates the memory effect of accumulators. For completely killed cans, it is not suitable.

Battery reanimation - proven in practice

As already noted, the main reason for the failure of nickel-cadmium batteries is drying out of the cans. The procedure for refilling them is not very pleasant, but not so complicated as not to be performed. We do everything as always - disassemble the case, take out the elements. We remove the paper with which the cans are wrapped. With some, it can be easily removed, whole, with some it has to be cut. We examine the body of the cells - some without any traces 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 depression in a circle, we make a hole. Distilled water will be required. We put it into a syringe, put the needle into the hole and very slowly pump water. It is not known how much of it will enter; it is impossible to visually determine it. If from the very beginning of the introduction of water from the jar, liquid flows, throw it out, it cannot be resuscitated, it must be replaced with a new element. There is some kind of reaction that 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 recovered, but this operation is harmful to health due to the toxicity of the contents. The reason for their failure is most often the violation of 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 the multimeter and look at the readings. If there is current, the reason is a break in the contact, you can continue the repair.

Cut off part of the metal on the cover protruding from the top of the element with pliers. We bend it upwards, and opposite the metal of the case, 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 do not know how to do this, do not take it - in this situation you will not learn, but spoil everything. Next, we seal the gap in the case with sealant - and for charging.

It can be done realistically if you use one of the above methods!

And needs to be replaced. Buying a new one is often difficult, and if it does, it is 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 repair 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

Accumulator blocks of household tools are almost the same in their device, regardless of the tool model (Bosch, Makita, Hitachi). They are packaged in a two-piece plastic case. The number of batteries may vary depending on the output voltage of the instrument being used. All elements are soldered in a specific sequence. The lead ends or terminals, at which battery voltage measurements are usually made, are brought out.

Most of the battery packs of a screwdriver or drill are designed in such a way that they are very easy to disassemble, regardless of whether we are repairing the Interskol screwdriver battery, or another model. Several fixing screws must be removed using a regular screwdriver. There are batteries that are difficult to disassemble, but lend themselves to a screwdriver and a pocket knife. 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 lie in the presence or absence of a thermal sensor, which automatically turns off the battery under critical heating conditions (above 50 ° C). The sensor constantly monitors the temperature not only under load, but also under 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.

There are a large number of inexpensive screwdriver models on the market.
Cheaper devices do not have such technical devices, and you need to monitor all processes yourself.

Types of battery repair

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

• express repair of batteries using the zapzapping method ;
• replacement of individual cells in the battery ;
• replacement of all elements of the battery pack .

Express repair of nickel-cadmium batteries using the zapzapping method

Translated from English, this means burning, applying short high current pulses 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 a high current. It is only possible to use high current if nickel-cadmium batteries are installed in the screwdriver. Other batteries (,) should not be exposed to such an effect.

The essence of the purge is to destroy the crystals that form inside the nickel-cadmium batteries with a high current. These crystals are called dendrites, and as they grow, the capacity of the battery will gradually decrease. "Pumping" with high currents quickly destroys the formed crystals and sharply reduces the self-discharge of the battery.

It is argued that zapzapping can be effective for any NiCd, even if they are completely discharged to zero or have been left without use for 10 or 20 years. The question is always about the likelihood of a successful repair in such "difficult" cases - when batteries are "repaired" in this way, it will either be successful or not. However, trying to revive them will not hurt. Observing the utmost care, of course.

To carry out zapzapping you will need:

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

Do not use an ordinary power supply as a charger. Even if the current strength of such chargers is 10-15 A, they will not withstand strong voltage. With a double-sided clamp, one terminal provides a tight contact, and the other terminal will hold the electrode itself. It is impossible to hold it with your fingers: during burning, it will glow hot. A zapping electrode is a piece of wire that is coiled 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 enthusiasts repair batteries using a regular soldering iron. But a spot soldering tool will be preferable when repairing. Protective equipment (gown, goggles, special non-flammable backing) is necessary because sparks always appear during high current blowing.

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 mix up the polarity, an important point.
• "Blow" 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 voltage readings after the first stage ... It should be raised to a maximum of 1.3 V. If the voltage is higher, the time of poking or their number should be reduced.

You need to poke very quickly and carefully, not allowing the electrode to weld even for a short time to the Ni Cd pole of the screwdriver battery, in order to avoid complete burning of the battery. It is recommended to put on a protective intermediate one on the positive electrode, or to 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 entire process, it is necessary to constantly monitor the temperature of the batteries. The intervals between zaps must be at least 15 minutes. Only in this case will the reanimated battery have a chance to extend its service life.

Replacing individual cells in the battery

If the battery capacity drops, it means that at least several of its cells are out of order. All batteries cannot "sit down" at once, so first you need to find the lowest-capacity 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, the type and capacity of which fully correspond to the previous ones. If there are nickel-cadmium batteries in the screwdriver, then it is worth purchasing 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"

The search for dead batteries in the circuit can be done in two ways:

• with a multimeter ;
.

For the first method, you only need a multimeter:

• charge the battery completely ;
• 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 elements with a cross where U is lower than nominal so as not to be confused with others;
• collect battery ;
• turn on the screwdriver ;
• work them until a noticeable decrease in power ;
• disassemble the battery again, measure the U values \u200b\u200bagain .

On batteries that are marked with a cross, the voltage "dips" will be much greater than in the rest - most often, below 1 V. As for the difference between the U values \u200b\u200bin the battery, if it is at least 0.5-0.7 V, this is essential.

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 completely discharged ;
• measure the voltage indicators at the terminals of all elements with a multimeter in turn .

"Dead" batteries are easy to separate because their voltage drops most after being discharged.

Repairs

So, the elements that were out of order 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 corrosive flux ;
• tin;
• copper plates (in case "relatives" broke during parsing) .

Spot welding in case partial renovation It is not necessary to use a battery. But during soldering, you need to be careful not to overheat the elements. It is best to connect the batteries with each other using the plates that they had. If they broke during the parsing of the battery into separate elements, then you will need to make new copper plates.

Do not forget about polarity. Each battery cell for a screwdriver is connected to the neighboring one according to the principle of a certain sequence. The minus of one can must be connected with the plus of another, and the minus of the other can must be connected with 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 at each element. If the soldering and the charging cycle were carried out correctly, then the multimeter will show approximately the same U figure on all batteries - 1.3 V.

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 in a screwdriver can be carried out in a way that requires minimal financial costs. If 18650 batteries are installed in the unit, it is realistic to borrow the same from an old non-working laptop, if possible.

Replacing all elements of the battery pack

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

You can completely replace all the cells of the battery pack with new nickel-cadmium batteries. They are much cheaper than nickel metal hydride batteries and, compared to other batteries, are the most tenacious and durable. Recently, however, the practice of self-alteration of batteries "from cadmium to lithium" is increasingly practiced, in other words, the installation of new lithium-ion batteries instead of old Ni-Cd.

Despite their reliability, nickel-cadmium batteries can fail quickly because they are daisy-chained to each other without a balancing board. If the batteries are of the same production batch, their parameters will still have a large scatter among themselves. With this connection, one cell will charge faster, another slower, and the third can be recharged.

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

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

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

Now the main thing is to properly solder the lithium . Cut the wires to the desired length, insulated, in silicone, very thick, to avoid melting when the lithium is heated. A knife is used to clean the areas of batteries for soldering.

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

Allow the batteries to cool down and combine the "pros" with "minuses" as usual. Check the total 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 is "short-circuited" during operation. The entire battery pack is bonded with heat-resistant tape specially designed to insulate batteries and their contacts.

The wires and connector are soldered. If the contacts are loose, they can be put on hot melt glue. 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 a battery for a screwdriver yourself. It will not only save financial resourcesbut will also facilitate the acquisition of valuable and useful skills.

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

The screwdriver is a special hand toolwhich is used to tighten and unscrew bolts, screws, nuts, screws and screws. Also, a similar device is used for high-quality and fast hole drilling and for the threading process. For modern craftsmen, the tool replaces a conventional screwdriver, only it saves a lot of time.

The tool is simply irreplaceable in a variety of construction processes, in renovation worksoh. If you need to assemble furniture, you cannot 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, the batteries have an identical structure. If you disassemble the battery, you can see that it is assembled from relatively small structural elements, assembled strictly in sequence.

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

The housing has four contacts. Among them, the following can be noted:

Two power ones, 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 disconnects and in a special way limits the charge current by raising the temperature to certain indicators. The heating process is carried out due to the sufficiently high currents during the implementation of the forced charge, that is, a special "fast" charging is carried out;
It can be noted the presence of the so-called "service" contact, which is connected through a special resistance. It is used for rather complex charging stations, which are designed to equalize the charge of all battery cells without exception. It should be noted that such stations are not needed in everyday life, since there is a high cost.

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

Approximately 70% of the total cost of a perfect new screwdriver comes from the battery, which usually comes with the kit.

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

What repair tools are needed

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

Ammeter 2 A;
tester;
voltmeter for 2 and 15 V;
ohmmeter;
milliammeter;
a 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 check, and it will also be necessary to analyze the parameters.

Features of repair technology

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

The supplied charger is defective;
The reason may be the strong deterioration of the battery;
There is a breakdown in strong contact between the installed terminals.

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

If the battery runs out of power quickly, before taking it apart and changing anything, try restoring the battery to its capacity first by doing a few deep discharge and full charge cycles. In 7 out of 10 cases, this helps restore battery capacity.

Often the cause of a breakdown is a faulty terminal. 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 sequential charges and discharges did not help, then it is worth replacing this important element for operation.

Below are the videos, it is 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 presents the battery recovery process itself.

Capacity recovery method

Often the battery of the battery needs to be restored to its capacity. This amount is usually lost due to the erasing of the memory effect. It is quite simple to define this problem. Once the battery is fully charged, it usually discharges very quickly and starts functioning again only after a certain time delay. It is quite easy to fix this problem. It is enough to follow the instructions below:

1. A small current is required to fully charge the battery.
2. Then discharge it completely, using a small load. Thus, it is possible to provide a slow, that is, relatively soft discharge, which will allow the outer layer and the entire plate to sink.
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 nominal capacity, that is, up to 5 V.

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

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

Various alternative solutions to the issue

There are some alternative options full recovery of the battery. Among them, the following techniques are very popular:

1. Gentle compression and slight deformation of the body. In other words, you can do what you did with the battery earlier, that is, compress it a little with light blows.
2. You can carry out the following process - the batteries are strongly charged with a stronger current. After that, they are completely discharged and recharged. Usually, such shock therapy gives a pretty good result, that is, it is able to bring back to life previously seemed hopeless batteries.

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

The nuances of self-repair

Do-it-yourself battery repair of such a tool as a screwdriver can be done by replacing all the faulty parts present. In the process of purchasing a new item, you must carefully ensure that the dimensions and capacity fully match all the original components. If you find a faulty component, you will need to cut it off, and then solder a new one in its place.

Speaking about the important points and 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 have been carried out, the potentials on the batteries can be completely different. Therefore, you need to align them. For this purpose, it will be necessary to charge the battery for 12 hours, then let it cool down 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 at the workshop and there is no need to purchase a new tool. To achieve the ideal quality result just follow the rules and the instructions above.

This video shows battery disassembly

Today, almost every good owner has a universal tool in his pantry or garage for assembling furniture, repairing a car and other equipment - a screwdriver. Unlike a power tool with a traditional power cord, it has a powerful battery and does not need to be connected to the mains. 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 will be to repair a screwdriver battery with your own hands, which will help to significantly reduce costs.

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

Connected screwdriver battery banks

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 connection to the memory. The supply voltage in household devices is 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, a temperature sensor and a thermal breaker can be located in the battery case, which 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 operation of the batteries under load.

Screwdriver battery types

Currently, the most popular and demanded manufacturers of screwdrivers are the following types:

Nickel cadmium batteries (NiCd).

Nickel-cadmium battery element of the screwdriver

The cathode of this cell is nickel hydrate with graphite powder and electrolyte. The anode is cadmium oxide hydrate Cd (OH) 2. 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 the nickel-cadmium battery of the screwdriver is about 15-25 years with an average number of charge-discharge cycles of 600 times.

To the benefits NiCd - batteries include:

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

- operation when not high temperaturesoh. Thanks to its 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;

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

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

- problems with disposal. 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 a battery of this kind is 8.4V, but over time it decreases to 7.2V. Compared to nickel-cadmium, NiMH batteries have 20% more capacity with an average of 250 discharge-charge cycles.

Benefits of NiMH Power Supplies:

- high capacity with a relatively low weight and dimensions;

- no memory effect. You may not fully charge the battery and with subsequent connections to the charger, the maximum capacity in the battery will be restored with complete discharge during operation;

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

- resistance to damage. With strong impacts, the NiMH cans are not destroyed and are able to work as before.

Disadvantages of Nickel-Metal Hydride Batteries:

- high level of self-discharge. During long-term storage, the battery is highly discharged and requires connection to the charger. To extend the battery life, it must be completely discharged and recharged;

- a small number of charge cycles. Unlike nickel-cadmium batteries, the number of discharge-charge cycles in 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 Power Supply for Screwdriver

Batteries of this type are widespread in consumer electronics and energy storage systems and are separated by a porous separator, an aluminum cathode and a copper foil anode. A charge carrier in such a battery is a charged lithium ion, which can be incorporated 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 battery model of the screwdriver.

Benefits of Lithium Ion Screwdriver Batteries:

- the ability to recharge at almost any stage of discharge without negative consequences in the future;

- 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 (shock);

- intolerance to overcharge when fully charged.

DIY screwdriver battery repair

When a power system malfunction occurs, the first step is to determine the cause of their occurrence. Almost all malfunctions associated with repairing a screwdriver battery can be eliminated by yourself. This does not require the use of a specialized tool and a set of plumbing screwdrivers and a soldering iron are enough.

Battery Troubleshooting

Having identified the faulty power supplies of the battery, 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 the event of electrolyte evaporation and charge them with a current with more high voltagedifferent from the nominal. The second way is to completely replace individual elements with new ones. Many experts recommend using the second way of solving 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 a defective battery bank can be restored only in power supplies with a "memory effect", which are nickel-metal hydride and nickel-cadmium cells. For these purposes, you need a professional charger with the ability to adjust the parameters of the current and voltage. We set a voltage of about 4 Volts on the charger panel with a current strength of 200mA and act exclusively on defective banks identified during battery diagnostics.

Filling the 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, take a thin drill up to 1.5 mm and pump out 1 cubic centimeter of electrolyte with a medical syringe. Add the same amount of water to the vacant space and seal the hole with sealant or epoxy resin... After connecting the cans into one circuit and assembling the case, we carry out the charging and discharging procedure 5-6 times in order to form the so-called "memory" in the power supply.

Replacing defective screwdriver battery cans

Connecting a new battery of the 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 an old can, it is necessary to leave a sufficient contact end 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 cell (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, except for disconnecting / connecting the control board.

DIY screwdriver battery repair was last modified: June 5th, 2019 by Administrator