How to quickly discharge the battery of an electric screwdriver
How to properly store batteries if one is in the screwdriver and the spare is separate?
Should you measure the voltage, if so, how often??
It is important to take into account the type of battery you have on your electric screwdriver and whether you use a new or an old one.
If your electric screwdriver has nickel-cadmium batteries (the battery), yes, they have that “memory effect.
that to bring the level of capacity of such batteries to a proper level, they have to be fully charged and fully discharged at least three times, thus you will remove the “memory effect” and the battery will last a long time.
And lithium-ion batteries are another case, they do not need pumping and have no “memory effect.
Such batteries just need to be recharged right after purchasing the tool and that’s it.
They do not like to discharge deeply, so it is necessary to charge them periodically, even if you do not use the screwdriver for a long time.
When charging any battery must comply with the temperature range from 10 to 40 degrees.
And most importantly, read the manual for the specific model of purchased screwdriver there is information on how to charge it correctly.ш
Currently, nickel-cadmium batteries rank first in popularity among manufacturers of power tools.
Ni-Cd batteries have low weight, insignificant dimensions, relatively low cost, but all this has one major disadvantage, the so-called “memory effect”.
Now take two minutes to stop reading and watch this video to better understand what the “memory effect” is and how it occurs.
That is, we ourselves are guilty in appearance of this effect, incorrectly serving a battery. we put it on a charge without waiting for complete discharge, but even we worsen the situation, not allowing it to be fully charged, we stop charging. So the battery “memorizes” these values and works within these values.
Hence the conclusion: it is necessary to observe the operating mode of the battery. to bring the battery to the maximum total discharge, and only then charge it with the parameters recommended by the manufacturers.
It is possible to “cure” a battery that has “fallen ill” with the memory effect.
There are special chargers for this purpose, which after connecting the battery first connect it to the load, dissipating the remainder of the charge, and then turns on the charging unit.
It is possible to “cure” the battery by your own efforts. In this case it is necessary to connect a 5 W 12-volt light bulb to the battery terminals and wait until it goes out. After that the battery should be fully charged.
To carry out such cycles will not two or three, it may be necessary to do a dozen of times to perform this procedure and, although a full restoration of the original capacity is unlikely to succeed, but the battery will work better. this is a fact!
Usually, buying an electric screwdriver, we tend to choose one with two batteries and, naturally, there is a question how to store the temporarily dead battery?
A battery that has been left idle for a short time (a week or two) can be stored at room temperature fully charged, but not in an electric screwdriver.
If the break in work will be long (about a month), it should be discharged, but not completely, otherwise it will develop irreversible processes. It is enough to work with an electric screwdriver to the stage when the number of revolutions at full load is noticeable and send it to rest. A preserved battery must undergo a “full discharge-full charge” cycle before it can be used.
If the battery has been stored for more than one month without use, the above cycles must be performed monthly.
Energy Storage Information Site
There are cases when the battery of the phone, electric screwdriver or other gadget needs to be urgently and completely discharged. You can use a capacitive program for the phone, screw a lot of screws into the board, achieving that the screen goes out or the tool fails. Is it always necessary to fully discharge a new smartphone battery and for what purpose? How to properly and quickly discharge any battery, using special programs, devices, tools?
To what voltage can the battery be discharged?
There is a concept of battery fully discharged in order to perform further operations and discharged to zero which requires resuscitation. How much the battery is discharged depends on the model and the number of cells in the battery. Cells connection in series, voltage on output terminals is summed up. This is why the discharge limit is different for acid, alkaline, and lithium batteries.
Do I have to fully discharge a new battery?? Yes, if it is a Ni-ion or Ni-MH battery. Such batteries have a memory effect. They must be fully discharged 3 to 5 times before they can be used and then recharged. Any further charging of this type of battery should be done after it has been fully discharged. Only store the battery fully discharged. How much can I discharge nickel batteries? A training cell is brought up to 0.9.1,0 В. Knowing the number of cells, you can calculate yourself, how many volts to discharge the battery.
People often ask if a new lithium-ion battery should be discharged. There is no memory effect in this type of galvanic cell. The device operates stably at moderate levels of charge. Therefore, it is possible to charge the battery at any convenient moment with a special charger. Is it possible to fully discharge a lithium-ion battery? It is possible, but after a discharge of less than 3.2 V special charging procedures must be applied; at 2.0 V the cell cannot be restored. A typical deep discharge is 2.5 volts per cell.
How many volts can a lead-acid battery pack be discharged to?? With a cell output voltage decrease of 1.70 V, the total voltage of a 6-cell battery is 10.3 V. A fully discharged battery will have a minimal reserve of survivability. Do I have to fully discharge an acid battery?? A maintenance-free calcium car battery can be destroyed even after a single deep discharge. All acid batteries after a deep discharge will inevitably lose some capacity due to plate sulfation.
Different types of batteries require a varied approach to maintenance. So whether you need to fully discharge the battery, new or in the process of calibration and testing, is written in the instruction manual of the device.
To what voltage may the battery be discharged?
There is a concept of a fully discharged battery in order to carry out further operations and discharged to zero, which requires resuscitation. How much battery voltage to discharge depends on the model and the number of bars in the battery. Cells connection in series, voltage on the output terminals is summed up. That’s why the limit of discharging is different for acid, alkaline and lithium batteries.
Do I have to fully discharge a new battery?? Yes, if it is a nickel-ion or nickel-metal hydride type battery. Such batteries have a memory effect. They should be fully discharged 3-5 times before use, then recharged. Any further charging of this type of battery must be done after it has been fully discharged. Only leave the battery fully discharged for storage. How far can I discharge nickel batteries?? A training cell is brought up to 0.9.1,0 В. Knowing the number of cells, you can calculate for yourself how many volts you need to discharge the battery.
People often ask whether a new lithium-ion battery pack should be discharged. There is no memory effect in this type of galvanic cell. The unit operates steadily at a medium level of charge. Therefore, you can charge the battery at any convenient moment with a special charger. Can I Discharge a Lithium-Ion Battery Fully? It is possible, but after the discharge below 3.2 V it is necessary to apply special charging methods, at 2.0 V it is impossible to recover the cell. Usually 2.5 volts per cell is considered a deep discharge.
How many volts can a lead-acid battery pack be discharged to?? With a cell output voltage decrease of 1.70V the total voltage of a 6 cell battery will be 10.3V. A fully discharged battery will have a minimal reserve of survivability. Do I have to fully discharge an acid battery?? A low-maintenance calcium car battery can go bad even after one deep discharge. All acid batteries are bound to lose some capacity following a deep discharge through plate sulfation.
Different battery types require different maintenance practices. Therefore, whether a battery needs to be completely discharged, new or in the process of calibration and testing, is written in the instruction manual.
How long to charge the battery of an electric screwdriver
Each electric tool is always supplied with an instruction manual that tells you exactly how long to charge the battery of an electric screwdriver. As mentioned before, the vast majority of modern battery chargers have charging level indicators, which makes them much easier to use. When the indicator light turns green or another color to signal the end of the battery charging time of an electric screwdriver, it is necessary to disconnect the battery in time.
The average time it takes to fully charge the battery is seven hours. And if the battery just needs recharging, it can be left on charge for 30 minutes. Although in the case of Ni Cd batteries, which have a “memory effect”, frequent and short recharging is not recommended.
There are several varieties of electric screwdriver battery chargers, depending on their application. A battery charger is usually included in the delivery of household power tools. Battery charging time with it varies from three to seven hours. There are also powerful pulse chargers that come with professional tools. How much to charge an electric screwdriver battery with such a device? “Pulsors” can fully charge a battery in an hour, which is their undeniable advantage. But of course the cost of such a tool is much higher.
Checking the condition of the battery with a multimeter
A tool like the STHT0-77364 can help you find faults in a variety of electrical components, including screwdriver batteries. To be reliable, it’s better to use it in combination with other testers. This allows you to check and calculate the error.
Note: Before you start measuring, you should make sure that the multimeter itself is working properly. All you have to do is plug it into an outlet along with another similar device and compare the readings.
A device that allows you to diagnose cell faults yourself.
- Test Light (Probe). equipped with two wires and allows you to detect breaks in the wiring of an electrical appliance.
- Arrow. a device with a digital scale and an arrow. These models are not very convenient to use. So that the numbers are clearly visible, the scale should be about the size of half a page. In addition, such testers are often characterized by confusing graduation and can only be worked with them in a horizontal position.
Tip: If you need an inexpensive multimeter, the 94W101 is fine.
- Digital. with LCD display. The scale shows only absolute values. The switch, as in the previous case, is manual. The tester is not suitable for alternating current.
- Automatic. as the name implies, this type of tester does not require you to change the regulator position manually. It is enough to specify the required value, using a special button.
Instruction: Electric screwdriver repair with your own hands: 2 types of faults
How long does it take to fully charge
How long does it take to charge a screwdriver battery?? It should be specified for what purpose it is charged. Manufacturers are looking to speed up charge times, to reduce interruptions and increase competitiveness. That’s why they set the maximum allowable charging current. Often sacrifice 10 to 20% of capacity at the end of the charge cycle.
This can be seen in the lithium battery charging graph. Where in the first hour you get 70% of its capacity, in the second hour you get another 20%, which is 90%, and the last 10% take another 1 hour, so 3 hours in total. And the “Bosch” OEM charger from China charges a lithium battery in only 30 minutes. With these subtleties in mind, it is now possible to answer the question posed.
You only need to charge the battery once to operate the tool. If necessary, it is not necessary to wait for the end of the charging time, and you can start working in half the time of standard charging. Single cases of undercharging do not have any negative effects.
Training cycles require charging the battery as much as possible, and even more so to restore its capacity. How can you do this with a regular charger when it automatically shuts off?? After voltage stabilization, after 20-30 minutes you can continue charging the battery on the regular charger again. It will take up another amount of energy. The charge cycle should be carried out up to three times. So the battery will be charged almost 100%. This is important so that in the subsequent training cycle the entire volume of the electrolyte will be used.
New Ni-Cd and Ni-MH cells are charged in 1 to 8 hours on a conventional charger, according to different manufacturers’ data sheets. This variation in time is caused by different settings of the magnitude of the charging current, depending on the position of the manufacturer in this matter. In addition, even chargers from the same manufacturer can have a variation of up to 2 hours due to setting errors, because at the end of the charge the current decreases extremely slowly. And the minimum current will always be.
Specialist in repair, maintenance of electrical equipment and industrial electronics.
Advice! The actual capacity decreases as the screwdriver is used for extended periods of time. It is useful to measure the charge time of new batteries after performing training cycles and record on the case. Comparing with the subsequent charge time after a year, two years, you can understand how much capacity the battery has lost.
New lithium (Li) batteries charge from 30 minutes to 120. It also depends on the charger settings of each manufacturer.
How long does it take to fully charge
How long does it take to charge a screwdriver battery? It is important to clarify for what purpose the battery is being charged. Manufacturers tend to speed up charging times, to reduce interruptions and increase competitiveness. That’s why they set the maximum allowed charging current. Often sacrifice 10-20% of the capacity at the end of the charging cycle.
This can be seen in the lithium battery charging graph. Where the first hour of charging takes 70% of the capacity, the second hour takes another 20%, which is 90%, and the last 10% takes another 1 hour, a total of 3 hours. And the regular charger “Bosch” from China charges a lithium battery in just 30 minutes. With these subtleties in mind, we can now answer the question posed.
You only need to charge the battery once for the tool to work. If necessary, you don’t have to wait for the end of the charge time, and you can start working in half the time of the standard charge. Undercharging the battery in isolated cases does not have negative consequences.
For training cycles it is necessary to charge the battery as much as possible and even more so to restore the battery capacity. How can this be done with the standard battery charger when it is automatically switched off?? After the voltage has stabilized, in 20-30 minutes you can continue charging the battery on the regular device again. It will take an additional amount of energy. You should run the charge cycle up to three times. So the battery is almost 100% charged. This is important so that in a subsequent training cycle the entire volume of the electrolyte is used.
New Ni-Cd and Ni-MH cells are charged with the standard device in 1 to 8 hours, according to different manufacturers’ data sheets. This variation in time is caused by different settings of the charging current, depending on the manufacturer’s position on this issue. In addition, even chargers from the same manufacturer may have a range of up to 2 hours due to inaccuracies in the settings, because at the final stage of charging current decreases extremely slowly. There will always be a minimum current.
Specialist in repair, maintenance of electrical equipment and industrial electronics.
Advice! The actual capacity decreases with prolonged use of the screwdriver. It is useful to measure the charging time of new batteries after practice cycles and record it on the case. Comparing with the subsequent time of charge after a year, two years, you can understand how much of the capacity the battery has lost.
New lithium (Li) batteries charge from 30 minutes to 120. It also depends on the charger settings of each manufacturer.
Rebuilding a Makita electric screwdriver with a lithium battery
There’s a Makita electric screwdriver with a 1.3Ah battery and 9.6V. To change the power supply on it to lithium-ion, you will need 3 18650 components. Modification will give the old tool new possibilities: it will increase the duration of work on a single charge, add power, because the operating voltage will rise to 10.8V.
The design will require the use of a BMS, a control controller that keeps the lithium cell operating within operating limits. With this breaker, each bank will charge evenly without exceeding 4.2V, the lower voltage is 2.7V. A built-in balancer is used here.
The parameters of the controller should accompany the operation of the tool with an increase in operating current to 10-20A. A 30A Sony VTC4 board with a capacity of 2100Ah can do the job without shutting down. Of the 20 amps fit Sanyo UR18650NSX taking energy of 2600A / h. The board is needed for the 3 elements, which is marked in the 3S classification. There should be 2 pins in the board, plus and minus. If the pins are marked with “P-“, “P”, “C-“, they are for later models of screwdrivers.
The step-by-step instructions for converting a Makita electric screwdriver to lithium batteries are as follows.
- You can disassemble the battery on the glue by tapping the connection with a hammer with a soft head on the weight. The direction of impact is downward, at the junction on the bottom of the housing.
- Take from the old assembly only the contact plates, carefully disconnecting them from the battery. Sensor and opener should be kept.
- Solder 3 cells in series, using TAGS flux and jumpers with insulation. Wire cross section must be greater than 0.75mm2.
- Assemble the circuit with the controller and connect the power unit with the contact plugs by wires of 1,5 square.
- Check the functionality of the circuit and reassemble the housing, planting it again on the glue.
In an electric screwdriver with an old DC9710 charger, the red LED on the panel will turn off after the lithium 18650 battery is finished charging. The charge level is monitored by the built-in controller.
The Makita DC1414 T charger is used to charge power sources for 7.2-14,4 В. While charging, the red light is on. But when charging a lithium battery, its voltage is not within the standards of salt products, and after 12 V the charger will start blinking red and green. But the right charge is already there. electric screwdriver is ready to work.
Features of different types of batteries charging
Charging different types of battery packs has its own nuances. They have to do with the properties of the materials from which the batteries are made.
In order to recharge the battery packs at regular intervals, pulse chargers are used. However, they can also be conventional. Professional power tools have the first type of adapters. The models for household use have the second type of adapters.
New batteries or those that have been discharged during storage must be properly charged before they are used. This is done on the basis of their specifications.
Say, nickel-cadmium batteries have a “memory effect”. They must immediately be charged three times in a row, and each time they must be completely discharged. Only then can the maximum capacity of the storage batteries be achieved. It will then be necessary to regularly connect the electric screwdriver to the charger if its power starts to drop to a minimum.
“Nickel-metal hydride batteries also have a “memory effect. Before using them for the first time, a full charge/discharge cycle should be repeated 4-5 times. And then when you use it, you must recharge it whenever necessary.
IMPORTANT! If you charge Ni-Cd and Ni-MH batteries incorrectly during the initial charge, their capacity will decrease.
There are no specific rules for lithium battery packs. They have no “memory effect. Lithium-ion battery packs can retain their original operating capacity level for very long periods of time. And there is no need to bring them to the state every time they are fully charged or discharged.
Methods of charging electric screwdriver batteries without using a special charger
Do not despair if the standard battery charger is unavailable or has failed completely. After all, there are many known methods of recharging batteries from other sources.
When no conventional battery charger is available, the battery of an electric screwdriver can be charged with:
optimal variant of the car charger is a device which can regulate the value of voltage and current. In these situations it is very important not to overcharge. For this reason, the charging current should be set to a range where the process goes from 0.5 to 0.1 Ah, depending on what the total capacitance is. Let’s say when it is 1.3 Ah, the amperage should be within the range of 650 to 130 mA.
The current values can be excessively high. It is not possible to set lower values with the regulator. In this case, an additional resistor should be used. A car lamp that should be connected in series to the battery pack is quite suitable.
IMPORTANT! Universal battery chargers are nice because they have many additional settings that allow you to find the best current settings to recharge your battery from any power tools.
For screwdrivers that are worn out, it is advisable to use external power sources. After all, from an economic point of view, it makes no sense for them to buy new batteries. The power tool only needs to be upgraded. It is important to have the proper connections. A good example of this is a converted USB charger which is also equipped with a fuse.
Nickel cadmium batteries do not have much of a memory effect. They can withstand sub-zero temperatures. They can hold a charge for a long time without any noticeable deterioration in performance.
But it’s important to mention their design features. After all, they are also the ones that form some negative failure factors.
Nickel-cadmium batteries. with electrolyte that gradually evaporates. This is why there are no methods capable of resuscitation in such a situation. The only thing left to do is to replace the battery.
And nickel-cadmium batteries also show high sensitivity to mechanical impacts. One of the two basic methods of possible resuscitation is based on this. The cell is recoverable by:
The last method requires some care. It is reasonable to look up the rated currents for a specific battery class. It is useful to study the experience of other users. That is, to ask how they carry out such reanimation measures.
How to store the battery. charged or discharged
Important! The general recommendation for all batteries is to store them in a cool place, at 10 to 15 degrees Celsius. Charge at 10. 20° C. Different types of battery should be stored at different charge levels.
Nickel-Cadmium (Ni-Cd) batteries
Keep in discharged condition. Charge level close to 10. 20%. Is conditioned by the self-discharge current and the memory effect provided that a deep discharge is not very damaging. In the discharged state, the self-discharge current is minimal. Discharge completely before use and then recharge fully after storage.
Nickel-metal hydride (Ni-MH)
Store in a fully charged, 100%. Afraid of deep discharge, after which the lost capacity is not restored. The memory effect is much lower than that of cadmium batteries. And the self-discharge current is 2 times higher, which will decrease the capacity of the charge up to 20% per month. Lose 100% of their charge in 6 months. To reduce the risk of deep discharge, keep them fully charged. Every 3 months, or more frequently if possible.
Lithium-ion (Li-ion) and polymer (Li-pol) batteries
Store half discharged, 40-50% of charge. The lower the storage temperature, the lower the self-discharge current.
What to do if the charge fails
If there is no charge in the battery, there may be the following reasons:
- Charger malfunction.
- No contact between battery and charger.
- Faulty protection sensor.
- The residual capacity is very low.
- Individual battery cell failure.
The efficiency of the charger can be checked with a voltmeter or another battery.
Batteries and chargers have 3 or more contacts. Auxiliary contacts provide connection to the protection sensor(s) located in the battery. Nickel cells have a thermal switch. If the battery reaches a temperature over 4050° the thermostat switches off the charger. The thermostat switch should be in the closed position. If it is always open, it is a sign of malfunction. It is possible to short the T terminals to the minus side of the battery and recharge without overheating protection. But it will be necessary to monitor the temperature of the battery and turn it off if the temperature is above 40°C. Lithium ones may have an entire integrated circuit with many safety features. They control not only the temperature of the cells, but also the degree of charge of each cell.
Failure of a single cell is indicated by the voltage of a charged battery. Even a battery that has no capacity should be charged to the rated voltage. If the nominal voltage is correct, then all cells have some capacity and deliver a voltage close to the nominal. Conduct training cycles: if the capacity increases, the battery is recoverable. Continue training cycles until charge and discharge times no longer increase.
When the voltage of a charged battery is a multiple of the voltage of 1 cell, there is a high probability of failure of the individual battery cells from which it is assembled. Disassemble the battery and test each cell. The defective ones are removed and the defective ones are soldered in their place. Two defective batteries can be replaced by one of the remaining serviceable cells.
What voltage and current is harmless to charge a car battery
To write this article we decided to write when we came across one of “service centers” on battery charging. The chargers are. diode bridge transformers. Even more disappointing are advices in the Internet: “unscrew the cans before charging”, “find charger with voltage 16V-16,5V”, “achieve good outgassing”, “charge with long low currents”.
Unscrew the plugs in the battery before charging (if there are any) we recommend to owners of Chinese or grandfather’s chargers. Such chargers are assembled according to the “transformer plus diode bridge” scheme. they can charge at any voltage, even at 20 volts. The boiling when charging the electrolyte may cause the case to burst.
Do not charge batteries that have been brought in from the cold, let them warm up indoors for a few hours. Do not charge batteries that are too hot either. Charging is most effective and safest at room temperature.
Practically useless to charge the battery discharged below 8 volts, most likely one of the cans in it is shorted or polarized. Regular charger will not be able to fully charge a highly unbalanced battery: the voltage on the current leads will not exceed 12.5-12.6 volts. Such batteries can only be cured (fully charged) by specialists. Charge the lagging weak banks separately at 2.4 volts with a current of 0.1 of the entire battery capacity in pulsed mode.
IMPORTANT ! Working voltages of the modern accumulator below which it is IMPOSSIBLE to discharge 10,8V and above which it is IMPOSSIBLE to raise while charging 14.4 В.
15-16 volt voltage, which charge most cheap Chinese chargers. it is a strong boiling, destroying the bubbles on the electrodes. The resulting sludge does not fall to the bottom, but remains on the plates, held by the separator envelopes. The access of the electrolyte to the active mass of the electrodes is partially blocked. Capacity and cold start current decrease.
In older battery designs. boiling while charging did not have this effect. Sludge has crumbled to the bottom. into its allotted place.
At voltage of 16 volts if you do not unscrew the battery caps and do not let the battery gases escape, the battery will simply inflate or crack its case. With normal charge voltage there is no need to unscrew the cap. Some batteries simply do not have them.
IMPORTANT! Faulty battery can be detected while charging. A dead battery is not capable of accepting charging currents higher than 1-2 Amps. The sign of the dead battery from strong sulfation: even on small charging currents voltage immediately rises to the maximum 14.4 volts. The battery voltage (12.7-13 V) gives the appearance of being fully charged. Worthlessness is indicated by the load fork test or the car starter. the voltage at the terminals drops instantly, the engine does not start. This sulphation is likely irreversible and the battery should be discarded.
IMPORTANT! Do not charge at currents higher than 1/10th of its capacity, also too low currents below 1/20th are useless. For standard 60 Ah batteries, normal charging currents range from 3A to 6A (7-9 Amps when charging in “current pause” mode). in the battery the charging current triggers chemical reactions. The reactions depend on the amount of active mass on the plates and its thickness, the electrode area, the temperature range, the undesirable process of electrolysis of water. a weak current will not charge the entire volume of the electrode, but only its uppermost layer. The voltage will then rise to 14V or more signalling the end of the charge. Water electrolysis will occur. Do not continue to charge such a battery at a low current, as passivation of the electrodes will occur. the plates will lose their ability to accept normal charging currents at all. Too high charging currents lead to undesirable chemical reactions in the battery, which in addition flow too violently and destructively. If the charging current is too high for a particular battery, the “extra current” causes an abundant release of hydrogen and oxygen from the electrolyte. boiling, “gurgling” in the cans. The bubbles are destroying the layer of the dressing, and the free oxygen is oxidizing the lead in the plus plates, turning them into soft easily destroyed by vibration lead oxide “spongy lead”. In a good battery, when you stop the current. the boiling should immediately stop.
It is also harmful to store the battery at a constant low current charge. If you charge an already charged battery. the positive plates will oxidize and the water will “boil off” from the electrolyte. The result will be a battery with corroded electrodes, loose bridges and high self-discharge.
The charging process should be monitored visually to make sure the electrolyte is not boiling, which is usually at voltages above 14.4 volts; and with a multimeter, by measuring the charging voltage and current. Cheap antimony batteries always boil. Also bubbles will appear when charging a sulfated battery. A weak charger (1-2 Amps) will not charge even a 60Ah battery. It will certainly raise the NRT of the battery to 12.7V, but it will add a lot of problems to the health of the battery. In case of more powerful automatic accumulators there is a problem of “excessive current” and rapidly increasing voltage, which leads to destructive for the battery electrolysis of water. It’s optimal to charge the battery even with “grandfather’s” charger plugged into the socket with the help of the timer in the drip charging mode: after a short period of current feed (10-30 sec) turn the charger off for a while (10 sec), then on again and then off again. This is how most of the rules for charging the battery are followed. charging is carried out with a strong current, the voltage does not rise prematurely, at the moment of disconnection of a battery charger the battery “assimilates” through chemical processes the charge received, the voltage does not rise too quickly, the process of “boiling” of water does not occur. The charging can be done with an electronic timer for switching the socket on and off, or you can charge it with a home-built multivibrator “blinker. The simplest blinker is made from a turn signal relay. Schematics are on the internet. On and off times are adjusted experimentally, based on the characteristics of the charger and the battery.
It is best to charge the battery with a modern “smart” charger that has “brains” inside. processor. Such charger is able to adjust the current and voltage of charging and can control them.
Know the charging time of your battery
The 12 volt vehicle battery is charged when the battery voltage and current do not change over 2 hours. For full operation it is enough to save the parameters for 1 hour. It is usually at 16.3 (±0.1) volts.
Check battery status with a multimeter
If the battery has a fault, you do not have to throw the battery away or have it repaired immediately. You can troubleshoot the problem yourself with the help of a multimeter and basic knowledge of electrical engineering. To do this you will need:
First, check the battery charger. The algorithm of actions is as follows:
- Turn on the device;
- Set the switch to constant voltage;
- Attach the probes to the sockets of the multimeter and connect them to the contacts and. of the charger;
- Then look at the screen of the device, and the readings are compared to those specified in the manual of the device.
- If the figures differ from the stated, then such a device should be repaired, or better to buy a new one.
To check the battery of an electric screwdriver, follow these steps:
- Full charging of the battery;
- Use a multimeter to check the battery voltage;
- If the readings differ, the battery is disassembled and the voltage of each cell is checked;
- If there are no damaged batteries, the voltage is checked on each battery individually;
- A load, such as a light bulb, is connected to each battery in turn;
- The battery with the reading dropping too much will be the faulty one.
For nickel batteries, a complete discharge is necessary before testing because of the memory effect.