This is a NiCAD battery charger circuit. High-quality, Not necessary
to have a full charge and cut, Because this circuit charges with
constant current and voltage regulated. But this circuit is not
difficult and cheap.
The basic principles of a NiCAD Battery charging. There are a number of ways, as follows.
1. A constant current.
The Nicad battery can provide current 500mA-hr charge rate that is
1/10 of the current capacity. Therefore should be charged with a
constant current 50mA for 10 hours, but actually want to charge for
14-16 hours because when near full current to charge less. So lasts
longer.
- In the NiCAD battery charger for fast charging current to about 100mA
charging rate for 3-5 hours. But it has the disadvantage of charging,
when the battery is fully charged, it must be removed, otherwise the
chemical substances in the battery will be very hot and damage.
- But a slow charger will not do, because it can withstand heat.
2.A constant voltage or Fixed voltage regulator
The NiCAD battery, each battery has a voltage 1.2V, when it is fully
charged voltage 1.25-1.3V. Therefore, we are charging a battery, the
plus the voltage additive, such as 4 pieces, then the charging voltage
1.2×4 = 4.8V. But the charge like this, at first, a very high current
flow. So, the voltage between NiCAD battery charger and very different,
may have caused overheating and damage.
3. The Current and Constant voltage.
Like this charging, devices little more than the two first, but high
quality. The safest way, and the battery the voltage is required by the
specifications. When fully charged, the charger can be left in, because
there is no current flow, Because the the voltage between the battery
as well.
- I so chose the charging current and Constant voltage.
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