If you have Sanyo CR14250SE batteries on your circuit. They are not recheargable. Check it out at sanyo.com. These have a ten year life and operate at the -40C to 60C range(unlike NiCad's pathetic range)supplying 3 volts at 850mA. You can replace them with any of the CR123 series battery. These supply 3v at >1000mA. The only replacement I have found are bigger than the 2/3AA size of the Sanyo, so solder wires to the board and run out of the VDO assembly. I have a modified battery holder and velcro to attach the batteries. Yan