Rechargeable battery circuit

[atomic.dave]

Would it be possible to draw power from USB and add a charging circuit to the battery?

[mightyohm]

Hi atomic dave,

A USB trickle charger is an interesting idea, but it would take some special circuitry to avoid overcharging the cells (easy to do since the geiger counter draws such little current). I'm not an expert on battery chargers, so I don't know of such a circuit, but there might be some examples online.