have i cooked my batteries by solar charging without a regulator?

[Shanaly]

they appear to now only charge to 8-9 volts! thanks for your ideas!

[Jon Hacking]

It's certainly possible, especially if your solar capability (in amps) is a substantial percentage of your battery capacity (in amp-hours). If your solar capacity is less than about 2% of your battery capacity, you probably won't cook wet-cell batteries (although you might need to top up the water). Gels & AGMs are a bit more delicate & don't tolerate higher voltages - & solar panels will quite happily continue supplying current up to ~17V!

If you have, say 300Ah of wet-cell battery capacity, you can probably install up to 6A of solar panels before you need a regulator. But regulators are cheap - you can get them for ~$30. Given the price of batteries, a regulator is probably a good investment.

We've posted an article on Solar Panels that you might find interesting.

[barnakiel]

Yes. Can be done. If they have ports, VERY CAREFULLY look inside (wear glasses) - the cooked ones will have tops of the plates dry.

b.