How to charge AA batteries. How to charge a battery at home: methods and devices
Did the battery from your camera, flashlight, children's toy or other necessary device suddenly run out? Such an eventuality cannot be foreseen. Unless you use special batteries with indicators. Or be careful not to carry a replacement with you. How to charge batteries at home? We will share with you useful instructions and recommendations.
What batteries can be charged?
Not every AA battery can be filled with energy using a homemade method. What batteries can be charged? Only finger alkaline (alkaline). But under no circumstances should you eat salt! The possibility of leakage or explosion of the product cannot be ruled out.
Method 1: Charger
We figured out whether the battery can be charged. If you constantly use such AA batteries, then the easiest way for you is to buy a special charger for them. Such a device will help to “breathe life” into the battery without unnecessary hassle.
However, the method also has significant drawbacks. Each charge reduces battery life by one third. In addition, the procedure may cause leakage of its composition.
Method 2: Power Supply
Let's look at how to charge batteries at home. For this method, you will need a power supply and wires to connect to it. Is everything in place? Here are the instructions for action:
When receiving a rechargeable AA battery using this method, pay attention to these recommendations:
- The process will not work if you reverse the polarity when connecting the wires. Moreover, in this way you will destroy the remaining charge in the element.
- Using the described method, the battery can be charged 1-2 times.
- The method is only suitable for finger-type alkaline cells!
- The procedure can be performed in any environmental conditions (with the exception of the freezer stage).
Method 3: Heating
You can also restore the battery charge by regular heating. But be careful - this method can cause the product to explode!
The simplest thing is this:
Method 4: Volume reduction
The method is quite incomprehensible and exotic at first glance. We need to reduce the size of the battery so that the charge in it is restored on its own.
What should you do for this? Mechanically reduce and make the body volume thinner. To do this, the battery is hit against something hard - asphalt, wall, stone, brick, etc. Or they simply trample on it with thick shoes. You can try to flatten it with a handy tool - for example, pliers.
This method will charge all AA batteries. It must be said that such a “barbaric” method helps restore the charge in some cases even to 100%!
Method 5: exposure to solutions
We continue to look at how to charge batteries at home. Within this method, two methods can be distinguished.
Instructions for the first:
How to charge batteries at home in another way:
- Use an awl or similar tool to make holes in the battery caps next to the carbon rod. The depth of each should be within 3/4 of the height of the entire battery.
- Pour liquid into the hole. You can take not ordinary water, but a solution of double vinegar or hydrochloric acid (no more than 8-10%).
- To sufficiently saturate the base, you need to repeat the pouring procedure several times, maintaining time intervals so that the composition has time to be absorbed.
- Finally, be sure to seal the holes. For these purposes, it is best to use resin or plasticine.
- Now you can use the battery - its charge should be restored to 70-80%.
Now you know how to charge a AA alkaline battery. Choose any method convenient for you. And, most importantly, be extremely careful! Careless actions may cause the battery to explode!
There comes a time in the life of each of us when we ask ourselves some question that is important to us.
For example: “Accumulators and batteries – what to choose?”
Although no, we have already solved this issue – batteries, of course!
A. here: “How to properly charge a car battery.” Stop! This is not what our site is about!
Cough cough... Hm... Ah! So here it is, the question!
How long does it take to charge batteries?
In fact, “how long to charge batteries” is one of the most important questions for every battery owner, since this directly determines how much electricity they will store and how long they will work (i.e., how many charge cycles). -discharge” they will withstand).
Ask the experts how to charge your batteries in a way that will extend their life.
So - here is the answer to the most important question - how long to charge the batteries so that they are fully charged and do not deteriorate?
And, in the end, how long does it take to charge AA batteries of different capacities?
If you have a charger with a constant charge current, then the time required to fully charge is calculated as follows: divide the battery capacity by the charge current of the charger (indicated on the device itself) and multiply by a special factor of 1.4 (since to charge, you need do the work.
And as with any work, part of the energy turns into heat). For example…
Having a battery with a capacity of 2700 mAh. , and a charger with a charging current of 200 mA., the full charging time will be
t=2700/200*1.4=19 hours
It must be kept in mind that this coefficient is correct for Ni (nickel) and Ni-MH (nickel metal hydride) batteries.
And finally, the easiest way out would be, of course, to let someone who already has a charger for AA/AAA batteries charge the batteries. And if this person owes you something and understands how this is done, then your problem is solved even easier.
If there is no such person, then buy yourself a charger - an “automatic” with the so-called “Delta-V”. Within the limits of the characteristics indicated on the device, you will receive an automatic charge of any battery whose type is supported by this charger.
All you need is to insert the discharged battery and remove the charged battery.
In this case, the question of how to charge the batteries is simply “shifted onto the shoulders” of the smart charger.
If this information was not enough, check out other articles on our site! It's all about power supplies and batteries!
1. Recharging of secondary batteries (batteries) must be carried out only when charger, which is intended for this!
The ideal option is when charging is specially selected for battery power sources in the store.
2. Fast recharging (30 minutes - 2 hours) with modern powerful chargers is not supported by all types of batteries. The slower the energy charge is delivered, the better.
3. Before you begin recharging, it is important to carefully read all included operating manuals and instructions in advance.
Moreover, such instructions must be attached to both the charger and direct rechargeable batteries.
4. Any new or old rechargeable battery must undergo so-called “training”. In fact, “training” is 3-4 full “discharge/charge” cycles.
Those. new rechargeable batteries must be recharged to the maximum and discharged to the minimum possible level (in this case, the battery charge should not be reduced to “zero”).
If your charger is really high-quality, then the “training” function is pre-installed in it. Such a charger is capable of independently carrying out the “training” process when selecting the appropriate option in the menu (read the instructions for the charger).
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If the “training” option is not provided in the memory, this process must be performed manually, monitoring all its stages. Three or four full cycles (automatically or manually) will be enough.
5. When recharging batteries, it is important to monitor the temperature of the batteries. This indicator (temperature) should not exceed 55 degrees Celsius (very hot to the touch).
Important nuance!
IMPORTANT: modern “smart” and programmable chargers that perform “fast” charging of batteries are able to automatically monitor the temperature of the charged elements, turning on the overheating protection system in time!
The battery should warm up, but not “boil”, which can lead to electrolyte leakage.
Those. Having plugged the batteries into the cheapest charger, the temperature must be controlled manually, periodically checking the heating level with the back of your hand.
6. If the battery has undergone “training”, it can be recharged without waiting for it to “go to zero”. In this case, it is worth talking about partial recharging during operation.
When working with lithium batteries, it is worth knowing that recharging is a natural procedure for them. And even lithium batteries are stored in a fully charged state.
Partial recharging is insurance against caking of the chemical composition of the battery!
7. There are no between nickel-cadmium and nickel-metal hydride battery chargers. Older models of Ni-Cd chargers are quite suitable for modern Ni-MH batteries, although the duration of the energy supply will increase slightly.
As for recharging Ni-Cd secondary current sources in a Ni-MH specification charger, this is possible, but not advisable, because High charging currents can reduce the service life of older battery models.
At the same time, old chargers are unlikely to be able to supply a modern battery with the required supply in less than 3-4 hours.
During engine operation, the rechargeable battery (), regardless of the type (maintained or maintenance-free battery), is recharged from the car generator. To control the battery charge, a device called a relay regulator is installed on the generator.
The very operation of a car in winter often involves short trips, turning on a large number of energy-intensive equipment (heated mirrors, windows, seats, etc.) The load on the battery increases significantly. At the same time, the battery simply does not have time to charge from the generator and compensate for the losses spent on launches. Taking into account the above, it is optimal to fully charge the battery with a charger to 100% at least once a year before the onset of cold weather.
Let us add that in case of problems with starting the engine due to engine malfunctions (problems with fuel equipment, etc.), the owner has to turn the starter much longer and more intensely. In such cases, you will need to charge the battery with an external charger much more often.
Charging the battery with a charger
To know how to charge a maintenance-free car battery with a charger, as well as charge a maintenance-free battery, you must follow certain rules. The charger (charger, external charger VZU, launch charger) is actually a capacitor charger.
Car battery - source DC. When connecting the battery, it is imperative to observe the polarity. For this purpose, the connection locations of the positive and negative terminals are indicated by the positive and negative signs (“+” and “–”) on the battery. The terminals on the charger have similar markings, which allows you to correctly connect the battery to the charger. In other words, the “plus” of the battery is connected to the “+” terminal of the charger, the “minus” on the battery is connected to the “-” output of the charger.
Please note that accidentally reversing the polarity will cause the battery to discharge instead of charging. It is also necessary to take into account that a deep discharge (the battery is completely drained) can in some cases damage the battery, as a result of which it may not be possible to charge such a battery using a charger.
It is also necessary to take into account that before connecting to the charger, the battery must be removed from the car and thoroughly cleaned of possible contaminants. Acid stains can be easily removed with a damp cloth, which is moistened in a solution with soda. To prepare the solution, 15-20 grams of soda per 150-200 grams of water is enough. The presence of acid will be indicated by foaming of the specified solution when applied to the battery case.
As for serviceable batteries, the plugs on the “cans” for filling acid should be unscrewed. The fact is that during charging, gases are formed in the battery, which must be provided with a free exit. You should also check the electrolyte level. If the level drops below normal, distilled water is added.
What voltage to charge a car battery with?
Let's start with the fact that charging a battery involves supplying it with such a current that the battery does not have enough for a full charge. Based on this statement, you can answer the questions with what current to charge the car battery, as well as how long to charge the car battery with a charger.
If a battery with a capacity of 50 Amp-hours is 50% charged, then at the initial stage the charging current should be set to 25 A, after which this current should be dynamically reduced. By the time the battery is fully charged, the current supply should stop. This principle of operation underlies automatic chargers, with which a car battery is charged on average in 4-6 hours. The only disadvantage of such memory devices is their high cost.
It is also worth highlighting semi-automatic type chargers and solutions that involve completely manual setting. The latter are the most affordable and widely available on sale. Taking into account the fact that the battery is usually 50% discharged, you can calculate how long to charge a maintenance-free car battery, and also understand how long it takes to charge a maintenance-free car battery.
The basis for calculating the battery charging time is the battery capacity. Knowing this parameter, the charging time is calculated quite simply. If the battery has a capacity of 50 Ah, then to fully charge it is necessary to apply a current of no more than 30 Ah to such a battery. The charger is set to 3A, which will require ten hours to fully charge the battery with the charger.
To be 100% sure that the battery is fully charged, after 10 hours you can set the charger current to 0.5 A, and then continue charging the battery for another 5-10 hours. This charging method does not pose a danger to car batteries, which have a large capacity. The downside is the need to charge the battery for about a day.
To save time and quickly charge the battery, you can set the charger to 8 A, and then charge it for about 3 hours. After this period, the charging current is reduced to 6 A and the battery is charged with this current for another 1 hour. As a result, it will take 4 hours to charge. Note that this charging mode is not optimal, since it is advisable to charge the battery with a small current of up to 3 A.
Charging with a high current can lead to overcharging and excessive heating of the battery, resulting in a significantly reduced battery life. We also note that the use of battery charging methods, which are aimed at minimizing the negative process of plate sulfation, in practice does not have noticeable positive results.
Proper operation of the battery depending on its type (maintained and maintenance-free), avoidance of deep discharge and timely charging using a charger allow the acid battery to operate properly for 3-7 years.
How to assess the condition and charge of a car battery
Proper charging and a number of conditions that must be observed during operation of a car battery can ensure normal engine starting even in extremely low temperatures. The main indicator of the condition of the battery is the degree of its charge. Next we will answer how to find out if the car battery is charged.
Let's start with the fact that some battery models have a special color indicator on the battery itself, which indicates whether the battery is charged or discharged. It is worth noting that this indicator is a very approximate indicator, by which only the need for recharging can be determined with a certain degree of probability. In other words, the charge indicator may indicate that the battery is charged, but the starting current at low temperatures is not enough.
Another way to determine the battery charge level is to measure the voltage at the battery terminals. This method also allows a very rough assessment of the state and degree of charge. To measure, the battery will need to be removed from the car or disconnected from the charger, after which you need to wait an additional 7 hours. The outside air temperature is not of fundamental importance.
- 12.8 V - 100% charge;
- 12.6 V-75% charge;
- 12.2 V-50% charge;
- 12.0 V-25% charge;
- A voltage drop of less than 11.8 V indicates a complete discharge of the battery.
You can also check the battery charge level without waiting. To do this, the voltage at the battery terminals must be measured by the load using so-called load forks. This method is more accurate and reliable. The specified plug is a voltmeter; a resistance is connected parallel to the voltmeter terminals. The resistance value is 0.018-0.020 Ohm for a battery with a capacity of 40-60 Ampere-hours.
The plug must be connected to the corresponding outputs on the battery, after which after 6-8 seconds. record the readings displayed by the voltmeter. Next, you can estimate the degree of charge of the battery by voltage using load fork:
- 10.5 V - 100% charge;
- 9.9 V - 75% charge;
- 9.3 V - 50% charge;
- 8.7 V - 25% charge;
- An indicator of less than 8.18 V means the battery is completely discharged;
You can also take measurements in the absence of a load plug without removing the battery from the car. The battery must be connected to the vehicle's on-board network. Then you will need to put a load on the battery by turning on the headlights and high beam headlights (for cars with standard halogen lamps). The headlight bulbs have a power of 50 W, the load is about 10 A. The voltage of a normally charged battery in this case should be about 11.2 V.
The next way to check the battery charge is to measure the voltage at the battery terminals at the moment when the internal combustion engine is started. These measurements can be considered reliable only if the starter is working normally.
At the time of start-up, the voltage reading should not be below 9.5 V. A voltage drop below this mark means that the battery is heavily discharged. In this case, it needs to be charged using a charger. This test method also allows you to identify starter problems. A known good and 100% charged battery is installed on the car, after which a measurement is made. If the voltage at the battery terminals at the time of starting drops below 9.5 V, then problems with the starter are obvious.
Finally, we add that the measurements in different ways suggest recording fluctuations in fractions of a volt. For this reason, increased demands are placed on the voltmeter. The accuracy of the device is extremely important, since the slightest error of even one or two percent will lead to an error in measuring the state of charge of the battery by 10 -20%. For measurements, it is recommended to use instruments with minimal error.
How to charge a completely dead car battery
A common cause of deep battery discharge is simple inattention. Often it is enough to leave the car with the lights or headlights, interior lighting or radio on for 6-12 hours, after which the battery is completely discharged. For this reason, many car owners are interested in the question of whether it is possible to restore a completely discharged battery.
As you know, completely discharging a battery greatly affects the battery life, especially if we talk about a maintenance-free battery. Manufacturers of car batteries indicate that even one full discharge is enough to cause the battery to fail. In practice, relatively new batteries can be restored at least 1 or 2 times after they are completely discharged without significant loss of performance properties.
First, you need to determine how much the battery is discharged using one of the above methods. You can also immediately charge the battery. Next, the completely discharged battery must be charged in the mode recommended by the battery manufacturer. The standard is to supply a charge current value at 0.1 of the total battery capacity.
A fully charged battery is charged with this current for at least 14-16 hours. For example, consider charging a battery with a capacity of 60 Amp-hours. In this case, the charge current should be on average from 3 A (slower) to 6 A (faster). A completely discharged car battery should be properly charged with the smallest current, and for as long as possible (about a day).
When the voltage at the battery terminals does not increase any more for 60 minutes. (assuming the same charging current is supplied), then the battery is fully charged. Maintenance-free batteries, when fully charged, assume a voltage value of 16.2±0.1 V. It should be borne in mind that this voltage value is standard, but it also depends on the battery capacity, charging current, electrolyte density in the battery, etc. Any voltmeter is suitable for measurement, regardless of the instrument’s error, since it is necessary to measure a constant, not an exact voltage.
How to charge a car battery if there is no charger
The most in a simple way Charging the battery involves starting the car using the “lighting” method from another car, after which you need to drive the car for about 20-30 minutes. For charging efficiency from the generator, either dynamic driving in high gears or driving in low gears is assumed.
The main condition is to maintain crankshaft speed at around 2900-3200 rpm. At the specified speed, the generator will provide the necessary current, which will allow you to recharge the battery. Note that this method is only suitable if the battery is partially, not deeply, discharged. Also, after the trip you will still need to fully charge the battery.
Quite often, car enthusiasts are interested in what else can be used to charge a car battery, besides a charger. Most often, chargers used to charge batteries are supposed to be used as a replacement. mobile phones, tablets, laptops and other gadgets. Let us immediately note that these solutions do not allow you to charge a car battery without a series of manipulations.
The fact is that the main condition for supplying current from the charger to the battery is that there must be a voltage at the output of the charger that will be greater than the voltage at the battery outputs. In other words, if the battery output voltage is 12 V, the charger output voltage should be 14 V. Regarding various devices, then the voltage of their batteries often does not exceed 7.0 V. Now imagine that you have a gadget charger at hand, which has the required voltage of 12 V. The problem will still be present, since the resistance of a car battery is measured in whole Ohms.
It turns out that connecting charging from mobile device to the battery outputs will actually represent a short circuit of the charging power supply terminals. The protection will be triggered in the unit, as a result of which such a charger will not supply current to the battery. In the absence of protection, there is a high probability of failure of the power supply from a significant load.
It is worth adding that the car battery should also not be charged from various power supplies, which have a suitable output voltage, but they are structurally unable to adjust the amount of current supplied. Only a special charger for a car battery is a device that has at its output the required voltage and current to charge the battery. In parallel with this, it is possible to control a constant current value.
Homemade charger for a car battery
Now let's move from theory to practice. Let's start with the fact that you can make a battery charger from a power supply from a third-party device with your own hands.
Please note that these actions pose a certain danger and are performed entirely at your own peril and risk. The administration of the resource does not bear any responsibility, the information is presented for informational purposes only!
There are several ways to make a charger. Let's take a quick look at the most common ones:
- Making a charger from a source that has a voltage of about 13-14 V at its output, and is also capable of providing a current of more than 1 Ampere. A laptop power supply is suitable for this task.
- Charging from a regular household electrical outlet of 220 Volts. To do this, you will need a semiconductor diode and an incandescent lamp, which are connected in series in a circuit.
It should be borne in mind that the use of such solutions means charging the battery using a current source. As a result, constant monitoring of the time and moment of the end of the battery charge is required. This control is carried out using regular voltage measurements at the battery terminals or counting the time for which the battery is charged.
Remember, overcharging the battery leads to an increase in the temperature inside the battery and the active release of hydrogen and oxygen. Boiling of the electrolyte in the battery “banks” causes the formation of an explosive mixture. If an electrical spark or other ignition source occurs, the battery may explode. Such an explosion can cause fires, burns and injuries!
Now let's focus on the most common method of self-manufacturing a charger for a car battery. We are talking about charging a laptop from the power supply. To complete the task, certain knowledge, skills and experience in the field of assembling simple electrical circuits. Otherwise, the best solution would be to contact a specialist, purchase a ready-made charger, or replace the battery with a new one.
The manufacturing scheme of the charger itself is quite simple. A ballast lamp is connected to the power supply, and the outputs of the homemade charger are connected to the battery outputs. A lamp with a small rating will be required as a “ballast”.
If you try to connect the power supply to the battery without using a ballast light bulb in the electrical circuit, then you can quickly damage both the power supply itself and the battery.
You should select the right lamp step by step, starting with the minimum ratings. To begin with, you can connect a low-power turn signal lamp, then a more powerful turn signal lamp, etc. Each lamp should be tested separately by connecting it in a circuit. If the light is on, then you can proceed to connecting an analogue with more power. This method will help not damage the power supply. Finally, let’s add that about charging the battery from such homemade device will indicate the burning of the ballast lamp. In other words, if the battery is charging, then the lamp will light, even if very dimly.
The new battery must be fully charged and operational, that is, it requires immediate installation on the car to begin further use. Before purchasing, it is necessary to check the battery according to a number of parameters:
- hull integrity;
- voltage measurement at the outputs;
- checking electrolyte density;
- date of manufacture of the battery;
At the initial stage it is necessary to remove protective film and inspect the body for cracks, leaks and other defects. If the slightest deviation from the norm is detected, it is recommended to replace the battery.
Then the voltage is measured at the terminals of the new battery. You can measure voltage with a voltmeter, but the accuracy of the device does not matter. The voltage should not be below 12 Volts. A voltage reading of 10.8 Volts indicates that the battery is completely discharged. This indicator is unacceptable for a new battery.
The density of the electrolyte is measured using a special fork. Also, the density parameter indirectly indicates the battery charge level. The final stage of testing is determining the release date of the battery. Batteries that were produced 6 months ago. You should not purchase back or more from the day of the planned purchase. The fact is that a ready-to-use battery has a tendency to self-discharge. For this reason, for long-term storage the battery must be prepared in advance, but in this case the battery can no longer be considered a new finished product.
It turns out that the answer to the question of whether a new car battery needs to be charged will be negative. There is no need to charge a new battery. If the battery you plan to purchase is discharged, then it may simply be old, used, or have a manufacturing defect.
Other questions regarding charging car batteries
Very often, during operation, owners try to charge the battery without removing the battery from the car. In other words, the battery is charged without removing the terminals directly on the car, that is, the battery remains connected to the vehicle network while charging.
Please note that when charging the battery, the voltage at the battery terminals may be around 16 V. This voltage indicator greatly depends on what type of charger is used during charging. Let us add that even turning off the ignition and removing the key from the lock does not mean that all devices in the car are de-energized. The security system or alarm system, multimedia head unit, interior lighting and other solutions can remain on or in standby mode.
Charging the battery without removing and disconnecting the terminals may result in too high a supply voltage being supplied to switched-on devices. The result is usually the failure of such devices. If your car has devices that cannot be completely de-energized after the ignition is turned off, then charging the battery without disconnecting the terminals is prohibited. Before charging in this case, it is necessary to disconnect the negative terminal.
Also, do not start disconnecting the battery from the positive terminal. The negative terminal on the battery is connected to the vehicle's electrical network through a direct connection to the body. Trying to turn off the “plus” first can have dire consequences. Unintentional contact of a wrench or other tool with metal parts of the vehicle body/engine will result in short circuit. This situation is quite common in cases where wrenches are used to unscrew the positive terminal from the battery terminal while the negative terminal is not removed.
As for charging the battery in the cold or indoors in winter without heating, the battery can be safely recharged in such conditions. During charging, the battery heats up, the temperature of the electrolyte in the “banks” will be positive. At the same time, it is necessary to bring the battery into a warm place for charging if the electrolyte inside the battery has frozen and the battery has been completely drained. Such a battery must be charged strictly after the frozen electrolyte has thawed.
For normal operation of any battery, you must always remember "The Three P's Rule":
- Don't overheat!
- Do not recharge!
- Do not overdischarge!
You can use the following formula to calculate the charging time for a NiMH or multi-cell battery:
Charging time (h) = Battery capacity (mAh) / Charger current (mA)
Example:
We have a battery with a capacity of 2000mAh. The charging current in our charger is 500mA. We divide the battery capacity by the charging current and get 2000/500=4. This means that at a current of 500 milliamps, our battery with a capacity of 2000 milliamp hours will charge to full capacity in 4 hours!
And now in more detail about the rules that you need to try to follow for the normal operation of a nickel-metal hydride (Ni-MH) battery:
- Store Ni-MH batteries with a small amount of charge (30 - 50% of its rated capacity).
- Nickel-metal hydride batteries are more sensitive to heat than nickel-cadmium (Ni-Cd) batteries, so do not overcharge them. Overloading can negatively affect the battery's current output (the battery's ability to hold and release its accumulated charge). If you have a smart charger with " Delta Peak"(interrupting the battery charge when the voltage peak is reached), then you can charge the batteries with virtually no risk of overcharging and destruction of them.
- Ni-MH (nickel metal hydride) batteries can (but not necessarily!) be “trained” after purchase. 4-6 charge/discharge cycles for batteries in a high-quality charger allows you to reach the limit of capacity that was lost during the transportation and storage of batteries in questionable conditions after leaving the manufacturing plant. The number of such cycles can be completely different for batteries from different manufacturers. High-quality batteries reach their capacity limit after only 1-2 cycles, while batteries of questionable quality with artificially high capacity cannot reach their capacity limit even after 50-100 charge/discharge cycles.
- After discharging or charging, try to let the battery cool to room temperature (~20 o C). Charging batteries at temperatures below 5 o C or above 50 o C can significantly affect battery life.
- If you want to discharge a Ni-MH battery, do not discharge it to less than 0.9V for each cell. When the voltage of nickel batteries drops below 0.9V per cell, most chargers with "minimal intelligence" cannot activate the charge mode. If your charger cannot recognize a deeply discharged cell (discharged less than 0.9V), then you should resort to using a “dumb” charger or connect the battery for a short time to a power source with a current of 100-150mA until the battery voltage reaches 0.9V.
- If you constantly use the same battery assembly in electronic device in recharging mode, then sometimes it is worth discharging each battery from the assembly to a voltage of 0.9V and fully charging it in an external charger. This complete cycling procedure should be performed once every 5-10 battery recharging cycles.
Charging table for typical Ni-MH batteries
| Element capacity | Standard size | Standard charging mode | Peak charge current | Maximum discharge current |
| 2000 mAh | A.A. | 200mA ~ 10 hours | 2000 mA | 10.0A |
| 2100 mAh | A.A. | 200mA ~ 10-11 hours | 2000 mA | 15.0A |
| 2500 mAh | A.A. | 250mA ~ 10-11 hours | 2500 mA | 20.0A |
| 2750 mAh | A.A. | 250mA ~ 10-12 hours | 2000 mA | 10.0A |
| 800 mAh | AAA | 100mA ~ 8-9 hours | 800 mA | 5.0 A |
| 1000 mAh | AAA | 100mA ~ 10-12 hours | 1000 mA | 5.0 A |
| 160 mAh | 1/3 AAA | 16mA ~ 14-16 hours | 160 mA | 480 mA |
| 400 mAh | 2/3 AAA | 50mA ~ 7-8 hours | 400 mA | 1200 mA |
| 250 mAh | 1/3 AA | 25mA ~ 14-16 hours | 250 mA | 750 mA |
| 700 mAh | 2/3 AA | 100mA ~ 7-8 hours | 500 mA | 1.0A |
| 850 mAh | FLAT | 100mA ~ 10-11 hours | 500 mA | 3.0A |
| 1100 mAh | 2/3 A | 100mA ~ 12-13 hours | 500 mA | 3.0A |
| 1200 mAh | 2/3 A | 100mA ~ 13-14 hours | 500 mA | 3.0A |
| 1300 mAh | 2/3 A | 100mA ~ 13-14 hours | 500 mA | 3.0A |
| 1500 mAh | 2/3 A | 100mA ~ 16-17 hours | 1.0A | 30.0 A |
| 2150 mAh | 4/5 A | 150mA ~ 14-16 hours | 1.5A | 10.0 A |
| 2700 mAh | A | 100mA ~ 26-27 hours | 1.5A | 10.0 A |
| 4200 mAh | Sub C | 420mA ~ 11-13 hours | 3.0A | 35.0 A |
| 4500 mAh | Sub C | 450mA ~ 11-13 hours | 3.0A | 35.0 A |
| 4000 mAh | 4/3 A | 500mA ~ 9-10 hours | 2.0A | 10.0 A |
| 5000 mAh | C | 500mA ~ 11-12 hours | 3.0A | 20.0 A |
| 10000 mAh | D | 600mA ~ 14-16 hours | 3.0A | 20.0 A |
The data in the table is valid for completely discharged batteries
