How to Restore the Electric Screwdriver Battery with Your Hands
The pricing policy of producers of chemical elements is frankly not encouraging. The cost of one electric screwdriver battery replacement can be as much as a third of a new tool. Therefore, you need to know what to do to fix it with your own hands, especially since most often it does not take much time.
Regardless of the form factor, there are three main types of batteries:
The charge goes through the typical power contacts “plus” and “minus”. There is another type of contacts. control contacts. They protect the banks of the chemical current source from overheating, leaking and further failure. They have a thermistor and a resistance.
How to make a ni-cd rechargeable battery recovery device
We separate the board from the case. Solder the pre-soldered wires to the button that triggers the flash.
This switch is needed in the future to discharge the internal capacitor completely with a flash.We also solder the wires to the outlet of the storage capacitor. Before this procedure always make sure that there is no charge on it. short-circuit with a screwdriver for example.
Then we solder these wires in series with the button and the battery holder. Plus from the capacitor. to the battery terminal.
How to rebuild simple nickel-cadmium batteries
The principle and the essence is the same as the previous one. to “break” the battery by a high current pulse. To do this, you need to assemble a reanimation unit with a high voltage generator and a storage capacitor. You will need:
- An old film camera (as long as the flash is working).
- Battery holder.
Disassemble the camera and separate the board from the housing. Solder the tinned wires to the flash triggering button. Then solder these wires to the switch.
Also solder the wire to the outlet of the storage capacitor. Before this procedure make sure that there is no charge on it (for example, short it with a screwdriver). Then solder these wires in series to the button and the battery holder. Connect the plus side of the battery to the plus side of the capacitor.
- Insert the batteries to power the board (these will actually power the improvised converter).
- Put the Ni-Cd battery into the battery holder.
- Power up the board. You usually hear a squeaking sound from the transformer when doing this. Wait until the capacitor is fully charged (this is indicated by an LED).
- Then immediately press the button that connects the circuit. battery-capacitor. You should hear a loud clicking sound (you should).
Time of the procedure, as in the previous variant. If necessary, repeat 2-3 times in a row.
Today on this subject there are many publications and videos on the Internet. In the vast majority of them are concerned with the restoration of the battery of an electric screwdriver, because batteries are expensive. often a little less expensive than the tool itself. In simple words Ni-Cd battery recovery is its starting (jogging) by short pulses at a high current, which in terms of power should be greater than the capacity of the battery itself.
- Serviceable battery. For example, from a car or uninterruptible power supply;
- alligator clips for “cigarette lightering” or pieces of wire of 10 cm cross section of not less than 1.5 mm2;
- multimeter to check the voltage;
Ideally perform the procedure separately on each battery. This way recovery will be less fast but more efficient.
- Find the minus-plus on the old battery or on the electric screwdriver unit.
- Then use wires and alligators to connect the minuses.
- Then attach the other end of the wire to one of the plus pins.
- After the free end of the wire, quickly touch the free plus. It is extremely important to do it briefly and very quickly (at least 3 touches per second). The whole cycle lasts no more than 4 seconds.
After one cycle, use a multimeter to measure the voltage directly on the battery to be regenerated. If it is not there, run the touch cycle again. When voltage appears, place the battery on a full charge of its capacity.
Rebuilding a screwdriver battery
Be warned right away that batteries with lithium-ion cells are not repairable. They can only be replaced.
Basic methods of restoring the parameters of individual batteries:
How to revive dead NiCd battery from cordless power tools
Restoring the battery through freezing
Nickel-cadmium batteries can be tried to restore a simple method of freezing. Let’s consider the order of actions:
- place the fully discharged battery in a plastic bag and place it in the freezer compartment of the domestic refrigerator;
- after 10-12 hours it is necessary to remove the battery from the freezer;
- put it on charge;
- After that, you need to plant the battery, that is to include it in the work until a complete loss of energy;
- repeat this operation 2-3 times.
If the attempt to restore the battery is not successful, it is necessary to resort to other methods.
Elimination of the memory effect
It is not very difficult to detect such a defect. Once the battery is fully charged, it quickly discharges and stops working. After some time it starts functioning again.
First it is necessary to fully carry out the process of charging, preferably with a small current (if possible). Then, fully discharge it at a low load. Such actions will not only allow the shrinkage of the top layer, but all the plates completely.
For the load you can use an ordinary light bulb with 60W power and 220V voltage. Discharge to 30% of the nominal capacity of about 5 V.
This procedure must be repeated at least five times before using the battery. Of course, this “treatment” will not fully restore the battery, but will extend its life for at least a year.
Adding the electrolyte
It is believed that the evaporation of the electrolyte is the most common problem of batteries.
To solve this problem, you need to dismantle the defective elements by cutting the connecting plates. After that, you need to make a small hole in the body of the cell (diameter up to 1 mm) on the side of the negative terminal. Then, using a medical syringe, add a few drops of distilled water. After that it is obligatory to perform qualitative sealing of the battery with epoxy resin. Insert the reanimated cell into the existing circuit.
In order to equalize the potential of all cells, they need to be discharged by a light bulb at 1.5 volts. The charge-discharge cycle should be done at least five times, only then use the tool.
The real way to restore to 100% of the battery of an electric screwdriver, according to my methodology NI-CAD 1.2V
I will start with the fact that on the Internet there are a lot of videos on battery recovery from screwdrivers, and they are all the same as a mirror, a brief description of the recovery process which offers these people, is that take the battery push it power supply or another battery, then charge and use, and strange that no one looks and what it will be at a voltage when it will lie a week or two. I propose a completely different way of restoration
Which does not just charge and use until the battery dies again. And you can use it like a new battery until you need it. This method was filmed in draft version about a month ago, but I did not dare to put it on the site, I just did not want to remake it for a better explanation. And the time I have to be honest recently very little free.
But time has passed which has shown that those versions of restoration which are offered to use very many in the network are not destined to live more than some time interval. And my version even after 2-1 months of downtime, as if nothing has happened quietly working and charged, I still tried to shoot a new video, which briefly will try to tell everything.
In fact, everything was very simple, and in this I was helped by the NI-CAD battery 1 which I disassembled.2V, which showed me that even with all zeros on the outside the patient is more alive than dead inside and feels very good.
The attempt to regenerate the tire relative to the current plate was done using distilled water and the process was quite successful, so I came up with the easiest way to regenerate them even without disassembling the batteries!
It is enough to drill a hole in the battery at the place of the rolling. and fill it up with 20.40 ml of distilled water. After a couple of cycles, we put a little silicone on the hole.
Before repeating I recommend to watch the video, where I tried to explain the process in more detail.
If you are not sure or are afraid of damaging the battery you can do this with one battery for example.
If your batteries have voltage and it is in the operating range, you may have a problem in the following :
If you notice that the drill is sluggish and runs as long after charging, you may have a problem with one or more batteries which are at zero!
Very interesting effect on battery capacity, it was equal or slightly greater than the specified capacity of the battery after restoration by this method.
What is the problem with ni cd batteries
Depending on their purpose, nickel cadmium batteries are made in cylindrical (“cans”) or flat (“pills”) forms. Their cathode is nickel oxide hydrate Ni(OH)2 with graphite powder, anode. cadmium oxide hydrate Cd(OH)2 or cadmium metal, electrolyte. potassium hydroxide KOH with the addition of lithium hydroxide LiOH. The design and the chemical processes involved determine the technical characteristics of the device, the advantages and disadvantages in comparison with other types of batteries.
The advantages of Ni-Cd batteries include:
- Higher power as compared to NiMH and Li-ion types, high charging and discharging currents;
- The possibility of operation in a wide temperature range, including the possibility of charging at low temperatures;
- the ability to withstand a complete discharge under heavy loads without consequences;
- the possibility of long-term storage in a discharged state without losing the ability to charge;
- lower cost.
The main disadvantage of Ni-Cd cells, causing problems and requiring attention during operation, is the “memory effect” phenomenon. If you charge a battery that is not fully discharged, Cd metal crystals begin to form on the electrode surface, resulting in increased internal resistance and decreased capacity. to prevent this problem, the battery should be fully discharged and then fully charged at least once a month.
Another problem with Ni-Cd batteries is the phenomenon of “thermal runaway” when charging. As the temperature of the electrolyte rises during charging, capacity increases, and the charger may overcharge the cell, resulting in a further increase in temperature and a further decrease in operating parameters. It is more preferable for Ni-Cd battery to use rapid pulse charging with electrolyte temperature control.
Charging for nickel cadmium batteries.
In addition to those listed, you can name other disadvantages of Ni-Cd battery cells:
- low specific capacity of such batteries;
- Bigger weight and dimensions in comparison with other types of batteries with the same capacity;
- problems with recycling and disposal due to high toxicity of cadmium.
Storage and Disposal
It is best to store nickel cadmium batteries in a discharged condition at a low temperature in a dry place. The lower the storage temperature of these batteries, the lower their self-discharge. Quality models can be stored for up to 5 years without significant damage to the technical characteristics. To put them into operation it is enough to charge them.
The harmful substances contained in one AA battery can contaminate approximately 20 square meters of land. For safe disposal of Ni Cd batteries, they must be handed over to recycling centers, where they are sent to factories where they must be destroyed in special sealed furnaces equipped with filters that capture toxic substances.