The NKHTs (nickel-cadmium sealed cylindrical) battery can replace an AA-size battery, but, unlike it, can be recharged. It can withstand several hundred charge-discharge cycles.
Instructions
Step 1
Before charging, it is advisable to discharge the batteries so that the voltage across each of them is about one volt. Deeper discharge spoils the elements, and insufficient discharge causes the so-called memory effect. If possible, discharge the batteries with low current separately to equalize the voltage across them.
Step 2
Make sure the charger you have (pre-made or homemade) is designed to work with the type of battery you are using (nickel-cadmium or nickel-metal hydride). A self-made device must necessarily work in a slow charging mode with a small current, which is one-tenth of the capacity, while a finished one can also be designed for fast charging. If the device is capable of switching charge currents, select the appropriate one for the batteries you have.
Step 3
If the charger is transformerless, never touch the contact springs when it is plugged in. A sure sign of a transformerless device is light weight, but it is best not to touch the springs of any device unless you are sure that it has a transformer. Insert the batteries into the device, observing the polarity. If the device is designed to charge batteries in pairs, their number must be even, and they themselves are distributed in pairs in adjacent sections. Now plug in the device.
Step 4
If the device is designed for slow charging, wait 15 hours, and if for a fast one, wait for the indication of the end of the charge to appear, or, depending on the type of device, wait the period of time specified in its instructions. After that, first disconnect the device from the mains, and only then remove the batteries.
Step 5
Return the batteries to the battery compartment of the device with which they are used, also observing the polarity of the connection. Make sure they are working properly. Never short-circuit the batteries.
