Is it possible to charge a lead acid car battery with a lab bench power supply?

I am thinking of hooking it up to 13.8 Volts and 1 Amps. Will this work?

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    \$\begingroup\$ Sounds good to me but 14.2 is used on flooded cells in cars to desulphate more. But 13.8 is good for float . keep in mind a low Battery will demand as much current as you can supply so overcurrent needs to be gracefully protected. ( by its design). You can make it graceful by current limiting with a 30W headlamp in series \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Sep 8 '18 at 17:37
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    \$\begingroup\$ 14.4 V to fully charge it at room temperature. 14.6 V for some gel and AGM types. Just don’t leave it at extended times at that high voltage. \$\endgroup\$ – winny Sep 8 '18 at 17:47
  • \$\begingroup\$ If your power supply has CC limiting you have no problems, simply set the voltage then connect the supply. If your supply has foldback current limiting, then you need to measure the current and slowly increase the voltage of the powers supply. If you place some resistance in series, then you'll never get close to your current without constant voltage adjustment. \$\endgroup\$ – Jack Creasey Sep 8 '18 at 17:48
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    \$\begingroup\$ Just a note to not do this indoors. Lead-acid batteries give off hydrogen gas while charging, which can be explosive. \$\endgroup\$ – rdtsc Sep 8 '18 at 19:44

If you are using flooded lead-acid, hook it up with 14.4v supply with even higher current. (Your car easily charges at 25 Amp). So, go ahead with 5 - 10Amps if your power supply can output. An advantage of trickle charging at 14.4V is, it will automatically balance out your cells. watch out for water level don't let it boil. For AGM, do not overcharge.

Also, do it outdoors as it produces hydrogen and some hydrogen sulfide.

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