The general rule is that you cannot charge batteries, but you can only do this with batteries. But there is an exception to this rule: you can still charge very small watch manganese-zinc and silver-zinc batteries.
Instructions
Step 1
Be sure to make sure your watch battery is indeed zinc-manganese or zinc-silver and not lithium. Do not try to charge the latter in any case - it is fire and explosive. Lithium batteries have designations starting with ML and CR, silver-zinc - SC, manganese-zinc - LR, AG. Also, the watch battery should be recently discharged and show no signs of corrosion. Regular (non-watch) batteries cannot be charged even if they are not lithium.
Step 2
Familiarize yourself with the pinout of the watch battery. A large contact, which occupies almost the entire area of the case, is usually positive, and a small one, similar to a ledge, is negative. In comparison, a conventional AA or AAA battery has the opposite polarity.
Step 3
From the materials at hand (clothespins, springs, coins, etc.), make a holder for a watch battery. Requirements for it are as follows:
- it must securely hold the battery even in case of shock;
- short circuit of the battery in case of its accidental shift must be completely excluded;
- in the absence of a clock battery, the power supply should not be short-circuited;
- the polarity of the clock battery connection must be clearly marked on the holder.
Step 4
Get a factory-made AA-size battery holder. Connect it with the positive terminal to the positive terminal of the homemade watch battery holder, and the negative terminal to the negative terminal. Mount all parts firmly on an insulating, non-combustible base.
Step 5
Insert the watch battery first, and then the regular one. The latter, in order to avoid exceeding the charging current, must be saline (not alkaline). Connect both batteries observing polarity. Close the device with an insulating non-flammable cover.
Step 6
Wait a few hours. Then disconnect first the regular and then the watch battery. Rearrange the latter in hours. It will be enough for a short time - about two months, and it will be possible to recharge it about three more times. A regular battery will be enough to recharge up to twenty hours.
