Battery Chargers, Can you over charge ? Options

[sjhowitson]

I have a battery charger a friend gave me. I want to plug it into the 914 for the winter to keep the battery charged. Can you over charge the battery? I don't know if the charger has an auto shut off or not. Anybody ???? (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif) (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif)

[lapuwali]

When you first start using your "tender", place a meter across the battery terminals to check the voltage, which should be 13.5-14v with the Tender hooked up. I've killed batteries with these things, including the brand-name "Battery Tender", which indicated it was charging when in fact it wasn't, and the battery was DIScharging through the tender. A few days later, totally flat battery.

Some of the Optima batteries can fool these things into providing a major surge of current when initially hooked up, as well. My reliable old 2A battery charger (not a trickle charger) will frequently trip it's internal thermal breaker when I first hook it up to an Optima, and will often cycle the breaker a few times until things stabilize and it delivers a steady 2A like it's supposed to. I'll not leave it on this charger for more than an hour or two.

If you disconnect the terminals on a fully charged battery, it should go for several weeks w/o losing its charge. Some batteries are better at this than others. Again, I've had good luck with Optimas going a long time w/o charging (2-3 months), and can be recovered with an hour on a normal charger at a low setting (1-2A).