diy solar

diy solar

Is It Okay To Use 2 Bench PSU's To Speed Up Top Balancing?

A.Justice

Swears he didn't start that fire.
Joined
Sep 12, 2020
Messages
1,561
Location
TN
Are there any issues with using 2 power supplies in parallel to top balance Lifepo4's? Both are set to 3.65 volts, 10.1 amps, and connected to opposing sides of the parallel battery bank. Both are the same brand and model.

The voltages read slightly different because one has slightly longer 10awg leads with ring connectors.

They were $20 off on Amazon, so I grabbed a second one, I figured they would be useful, especially because I can be impatient.
 

Attachments

  • 20210502_191356.jpg
    20210502_191356.jpg
    289.4 KB · Views: 13
I'd use the two but set them a bit lower, to 3.45V each, and get the cells to that point at 20A or so.

Then remove one and step up to your final top voltage. 3.65V is a bit high, I prefer to get to 3.5V and call it done. Not much power left above that.
 
I see no issues with using both together. Or you could split the pack if you like. Could have one for each cell if you really want to get busy.
 
I use regulated bench power supplies regularly. Both turned on in constant voltage mode at 3.65v, it will not give you any issues. Once anything gets up to 3.65v, whichever one senses that first will start tapering back current. They aren't like 3 stage smart battery chargers that need accurate voltage measurements, and you should be going until the current tapers down to 0, at which point v=ir, your voltage drop is 0, and the length of your leads does not matter at all.

Unless the power supplies are not regulating properly...Which is doubtful if you just bought them and have tested them out at all.
 
Yes, generally speaking it will work fine. There can be some oddball power supplies that can have problems, just hook them up, set the voltage, and connect the leads.
 
Back
Top