RECHARGEABLE BATTERY

Sealed alkaline nucleotidase (NiCd) and Nickel-metallgidridnye (NiMH) batteries are finding increasing application not only in industrial devices but also in home appliances, replacing batteries size AA and AAA. But these batteries, like any other, eventually “emptied” and require charging. To recharge, as recommended by the instructions for use and marking of the batteries themselves, through them must pass through the current ICT = 0.1 mA from the numerical value of the nominal capacity C for 12 — 16 hours.

But what if a suitable current or “smart” electronic charger and a simple transformerless available charge current differs from the value of batteries? To estimate the charging time is definitely unlikely to succeed. And if you define it by eye, when incomplete charging capabilities of the batteries will be limited but if excessive shortens the life and even the possibility of their explosion!

 

So that when you use not native charger, in which the charging current Iz is different from the standard (0,1), we offer a charging time t s to determine using a special formula. At its conclusion based on the following main points:

1. The charging time t s (h) is inversely proportional to the charging current I (A or mA) and is directly proportional to battery capacity (Ah or mAh).

 

2. The charging current should not be more than that allowed for “fast charging” IB. If not specified, then make it equal to 0.25 of the numerical value of capacity. (Before you use the charger, measure the current “de facto” — it can differ from the nameplate values).

 

3. When servicing of the battery is the main part of the current goes directly to the charge — electrochemical processes, and the other part is spent on support work and related phenomena: the movement of ions, heat and other losses.

 

It follows from the foregoing that the theoretical “ideal” charging time can be determined by the formula:

 

t s=C/I (1).