Can i charge 12V 15Ah sealed lead acid battery by giving 60V 4A to it's terminals ?
Oh, reddvoid! STOP! Do NOT apply SIXTY VOLTS with a FOUR AMP capacity to your 12 volt battery! If you do so, expect maximum smoke, fire, and possibly an explosion spraying sulfuric acid all around.
“Lead acid batteries should be charged in three stages, which are  constant-current charge,  topping charge and  float charge. The constant-current charge applies the bulk of the charge and takes up roughly half of the required charge time; the topping charge continues at a lower charge current and provides saturation, and the float charge compensates for the loss caused by self-discharge.”
“Overcharging with high charging voltages generates oxygen and hydrogen gas by electrolysis of water,
These are general voltage ranges for six-cell lead-acid batteries:
Typical (daily) charging: 14.2 V to 14.4 V”
Oh, I had just posted this and now see that pantaz has posted one of the same references!
Thanks bobywhy, you saved my day :)
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