NiMh cells are widely advertised as having high energy content and not afraid of cold. But, unfortunately, these elements have memory, and their capacity drops with each charge. Quality chargers can prevent this, but they are very hard to find. Therefore, exercise your batteries periodically.
Necessary
- - Charger;
- - light bulbs;
- - skills in working with electrical engineering.
Instructions
Step 1
Perform a NiMh workout, which consists of several (one to three) full discharge and recharge cycles. Discharge until the voltage across the cell drops to 1V. Discharge cells individually. The fact is that there may be a different ability to take charge from each battery. This is amplified at the moment of charging without training.
Step 2
Perform discharge in a special device that can perform it individually for each battery. If it does not have a voltage monitoring indicator, monitor the brightness of the light bulb and discharge until it drops noticeably. Time the light bulb on to determine the battery capacity.
Step 3
Use a formula where the capacity is equal to the product of the discharge current and the discharge time. Accordingly, if you have a battery with a capacity of 2500 mA, capable of delivering a current of 0.75A to the load in 3.3 hours. If, as a result of discharging, the time is shorter, then the residual capacity is also less. If the capacity you need drops, continue exercising the battery.
Step 4
Discharge the elements using a device made according to the scheme https://www.electrosad.ru/Sovet/imagesSovet/NiMH4.png. You can design it based on an old charger. There are only four bulbs in it. In case the lamp has a discharge current equal to or less than the battery, use it as a load and indicator. In other cases, it is only an indicator during battery recovery.
Step 5
Set the resistor value so that the total resistance is about 1.6 ohms. Do not replace a light bulb with an LED. For example, you can take a krypton bulb from a 2.4V flashlight. After fully discharging each battery, charge it. For two batteries with a voltage of 1.2 V, charge with a voltage of no more than 5-6 V. The duration of the initial boost charge is usually from one to ten minutes.
