Yes, definetely : the source battery always has to be of a greater voltage (even if it is slightly) compared to the charging battery, in order to be able to fill it up.
Just take care that the charging tension tends to fall down rapidly once disconnected (you can check that by leaving a multitester's probes attached for a moment): that's why, for example, a 9v battery should be charged around 10.5-11v.
Anyway, the more you'll charge a battery, the more it should become responsive to a radiant charge (that's called : conditionning, and it's a know fact among such system's users).
Lots of observations still to do to understand and try to "master" your system, but that's a good start. Congrats.
Just take care that the charging tension tends to fall down rapidly once disconnected (you can check that by leaving a multitester's probes attached for a moment): that's why, for example, a 9v battery should be charged around 10.5-11v.
Anyway, the more you'll charge a battery, the more it should become responsive to a radiant charge (that's called : conditionning, and it's a know fact among such system's users).
Lots of observations still to do to understand and try to "master" your system, but that's a good start. Congrats.
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