Rechargeable batteries - how long do you need to charge them?

In new portable gadgets, power sources are increasingly being supplied not by conventional batteries, but by rechargeable batteries. They are more expensive in price, but overall there is a saving, since the elements are rechargeable. Savings, however, will only occur if you use batteries correctly. Otherwise, they will “live” even less than conventional galvanic cells. In the article we will look at how long it takes to charge batteries of different capacities, and how to determine the degree of charge.

Proper charging of batteries can extend their life.

How long does it take to charge batteries?

The charging time can be determined by dividing the battery capacity by the charger current. In this case, it is important to take into account the coefficients of conversion of electricity into heat, energy dissipation coefficients, which take values ​​from 1.2 to 1.6.

The charge coefficient can be taken from the calculation of the ratio of the charge current to the battery capacity. The greater this difference, the larger the coefficient should be used.

Note: the online calculator “how long to charge batteries”, located above this article on our website battery.rf, works in a similar way.

Additional Tips

Depending on the battery device, they may take different amounts of time to charge:

  • An acid battery made of lead and used in a car is charged with a current of 0.1 of the rated value. The time is ten o'clock. If the capacity is 50 A/h, then a current of 5 A is required. The condition of the lead plates will not deteriorate from a full charge.

Lead acid battery

  • Another type is nickel-cadmium batteries. Types: finger and little finger. For the charging procedure, chargers are used, which indicate the required current value. To determine the time, use the calculation method described above.

Nickel-cadmium batteries

  • Polymer batteries made from lithium. The battery is charged using pulsed currents. Charge control is carried out using the charger processor. The time depends on the current. The time range is 30-60 minutes.

Lithium polymer batteries

The first two types of batteries must be fully charged. But the last type does not need to be charged; a full charge is murder for them.

This is interesting: What should the coolant temperature be?

Features of the formula

The above formula:

charging time = (battery capacity / charging current) * coefficient

is advisable if the following conditions are met:

1. The battery charge time is within 4-20 hours, no more and no less.

If the charging time is less than 4 hours: a full-fledged charger that supplies similar currents must automatically stop supplying electric current. The battery can then be removed and used.

If the charging time is more than 20 hours: there is no point in worrying about harm to the batteries. Such low charging currents will not harm the batteries.

Moreover, the battery can remain in low-power chargers for almost a whole week! (6-7 full days without visible damage to the battery).

2. Battery capacity - indicated on the packaging, on the case, in the attached documentation, in the instructions, on the battery case. Units of measurement are mAh (milliamp-hours, ampere-hours).

3. Charging current - indicated on the case, in the instructions, in the documentation, set manually, reflected on the display (if any) of the charger. Units of measurement are mA (milliamps, amperes).

Lithium-ion battery (li-ion)

An important characteristic of the charger is the charge current:

  • with low current - gentle mode, there will be no overheating, but charging may take up to a day;
  • with average current - do not heat up, practically do not affect the service life, charging lasts about 6 hours;
  • with high current - very fast charging in a few hours, but if the battery is of poor quality, it can quickly become unusable.

Attention is also paid to the possibility of memorization. Chargers with intelligence function select the appropriate mode and time.

There is no need to perform any special manipulations. Most chargers are powered by AC power, so the voltage needs to be more or less stable. Batteries can be charged at any stage, but it is advisable to complete the charging cycle (this protects the filling from rapid deterioration). The main thing is not to confuse the polarity.

There is no particular difference between AA batteries from different manufacturers. The main thing is to pay attention to the type of power source and the difference in capacity. Devices from Eneloop, Robiton, Varta, GP, Duracell, Xiaomi, Camelion have a good quality-to-price ratio.

Battery AA NiСd

First of all, you need to pay attention to the type and decoding of the values. Depending on the device for which AA AA batteries are selected. You should also pay attention to:

  • current strength;
  • voltage (from 1.25 to 3.7 Volts);
  • capacity;
  • power;
  • life time;
  • charge-discharge cycle;
  • operating temperature range.

A properly selected device can last up to 20 years. Of course, this period depends on the intensity of use.

We often miss good shots in the forest or at sea, we may be late or stumble in the dark because a simple battery from a camera, watch or flashlight suddenly runs out. It's hard to say exactly when the charge will be used up, unless this is a Duracell model with an indicator. But don't despair! Thanks to a few tips, you can avoid unpredictable situations and take the intended photographs from a digital camera, find out the exact time, illuminate the road, etc. In this article, we will tell you how to charge batteries at home without a charger, which will make life much easier in unpredictable situations.

Know that to charge alkaline batteries you can use a special charger that can relatively quickly restore a discharged item. But each charging session will reduce its operating life by approximately 1/3. In addition, leakage is possible.

Note! At home you can charge: alkaline (alkaline) AA batteries. Don't: salt. The possibility of leakage or even explosion cannot be ruled out!

Charging can be done using various methods. Therefore, you should not throw away an element as soon as it stops serving. A few recommendations - and he is back in action. The first method, using which you can charge AA batteries yourself without a charger. We connect the power supply to the network. Next, using the connection wires, we connect the used battery to the unit. Don't forget about polarity: plus is connected to plus, and minus is connected to minus. It’s quite easy to find where the “-\+” of a discharged object is: they are marked on the body.

Having connected the battery to the power source, wait until it warms up to fifty degrees and turn off the power. Next, wait a few minutes for the heated object to cool down. Otherwise, it may explode. Then, while the AA is still warm, it needs to be charged in a different way. It consists of the following: connect the power supply to electricity and disconnect it. This should take about 120 seconds. Next, we place the object to be charged in the “freezer” for 10 minutes, then take it out and wait 2-3 minutes for it to warm up. That's it, the charge is restored right at home without a charger! You can safely use it for the same computer mouse.

Main rules:

  1. The charge is not feasible if you arrange the + and - in a different way. On the contrary, the battery will drain even faster.
  2. It is permissible to charge the object at home 1-2 times.
  3. Using the method described above, you can only charge simple AA alkaline batteries.
  4. The charge can be carried out in any ambient temperature conditions.

Another charging method is the conventional heating method. But it is fraught with consequences (explosion). In this way, you can restore, again, small alkaline batteries at home. You can also charge them in a simpler way - place discharged objects in hot water, but for no more than 20 seconds, otherwise sad results are possible. Another simple way is to flatten or reduce the volume of the element with your own hands. This way you can charge various AA batteries. There is an example when a person, after the charge of a cast-ion battery had expired, simply took it out and stomped on it, after which the charge indicator showed one hundred percent.

You can also restore the charge without a charger this way: we make 2 holes with an awl near each carbon rod with a depth of three-quarters of the height of the element itself. We pour liquid into them and seal them, covering them with resin or plasticine. You can pour not just liquid, but an eight to ten percent solution of hydrochloric acid or double vinegar. Pour the solution several times to ensure sufficient saturation. This method allows you to charge up to seventy to eighty percent of the initial capacity.

Video instructions for restoring Duracell using phone charging

Another way to charge the product: open the cell cover with a knife. If the zinc cylinder, the object's rod and the carbon powder are intact, then immerse the object in the salt solution. Its ratio is as follows: 2 tablespoons of table salt per several glasses of liquid. Next, boil the solution together with the element for about ten to fifteen minutes. Then we return the gaskets responsible for sealing to their place and cover them with wax or plasticine.

In the modern world there are many devices and rechargeable batteries are already a necessity. While some people change one battery after another, others simply charge the battery. In order for the product to last as long as possible, it is necessary to follow the recommendations for charging and operation and select them in accordance with the requirements of the devices.


Time definition examples

Given: Battery capacity - 1000 mAh Charger current - 150 mAh Coefficient - 1.2-1.6 (1.4 average) Charging time - (1000/150) * 1.4 = 9.3 hours (9 hours 15 -20 minutes).

This will be the AVERAGE charging time, because... we took the average coefficient - 1.4 (the same value is in the online calculator)!

In this case, the battery charging speed may vary depending on:

  • temperature;
  • chemical composition of batteries;
  • initial charge stored in the battery.

Microprocessor charger: charging with brains

Devices with a microprocessor are more expensive, which is why they are most often used by those who need batteries for their occupation. For example, photographers. But the prices are by no means astronomical, so nothing prevents you from making a choice in favor of a smart charger. How is it usually better?

  • Has settings . You can independently set the optimal current for a specific battery.
  • Has independent channels . You can charge only one battery, or you can have a battery with a capacity of 1600 mAh in one slot, and a battery with a capacity of 1600 mAh in the other, and both will be charged 100%.
  • Has foolproof and overheating protection . They simply won't turn on until you place the batteries in the correct way and will turn off if the battery gets too hot.
  • Has special modes . For example, “Training” - successive cycles of charging and discharging the battery in order to restore its capacity.
  • Has a display . You see all the information about the accumulated capacity, voltage, current...

Number of cycles

It is worth remembering that each time you recharge a battery, its service life deteriorates. Thus, for nickel-cadmium batteries no more than 1000-1500 discharge/charge cycles are allowed.

For modern batteries, they are trying to increase this figure, bringing it to 4000 cycles. And if a brand new rechargeable battery has completed the full “training” course 3-4 times, then it is considered that it has reached performance characteristics that will be maintained throughout its entire service life.

You can learn about how to properly use rechargeable batteries, precautions and other tricks:

  • in technical documentation;
  • in the operating instructions;
  • in the articles on our site.

The lifespan of an average rechargeable battery is 3 years.

NI-MH batteries with low self-discharge

This is a fairly new technology. The abbreviation LSD is sometimes used. What is translated from English as “low self-discharge” - low self-discharge .

Such batteries appeared on sale a little over 10 years ago and have proven themselves very well. Compared to conventional batteries, they have lower internal resistance and, as a result, higher discharge currents. Their capacity is slightly lower than that of conventional NI-MH batteries. But due to the fact that a regular battery has a self-discharge of about 10% in the first day, they are no less effective.

It is quite easy to distinguish such a battery from a regular one. There will be an inscription “ready to use” on the packaging and on the item itself, i.e. “ready to use.” Such elements are sold already charged. This is the optimal choice for amateur photography, when the task is not to take several thousand frames in one day.

( 1 rating, average 4 out of 5 )
Did you like the article? Share with friends:
For any suggestions regarding the site: [email protected]
Для любых предложений по сайту: [email protected]