from the optima web site:
http://www.optimabatteries.com/publish/o...ical_specs.html
<font color="red">Safety Information:
Always wear safety glasses when working with batteries.
Always use a voltage regulated battery charger with limits set to the above ratings. Overcharging can cause the safety valves to open and battery gasses to escape, resulting in premature failure. These gasses are flammable! You cannot replace water in sealed batteries that have been overcharged. Any battery that becomes very hot or makes a hissing sound while recharging should be disconnected immediately.
Failure to fully charge a battery can result in poor performance and a reduction in capacity.
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