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DIY Battery Woes
#11
Thank you for the input. I have one last question:

If I have a functional battery that is charging and discharging properly, If I choose to use the speaker connected to the 24v switching power supply, can the battery be wired up to that as well? Will it be damaged in any way, should I put a switch on the battery to take it out of the circuit for when I use the power supply?
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#12
You cant parallell the PSU and the battery. You can attach the Charger and use it though. Unless you PSU is intended as a Charger?

Perhaps om missing something
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#13
(11-11-2020, 03:35 AM)meanjeans Wrote: Thank you for the input. I have one last question:

If I have a functional battery that is charging and discharging properly, If I choose to use the speaker connected to the 24v switching power supply, can the battery be wired up to that as well? Will it be damaged in any way, should I put a switch on the battery to take it out of the circuit for when I use the power supply?

A typical switching power supply is not a charger, ie it won't self limit it's output current well & may shut off or overheat if the current the batteries pull is too high. You also risk putting too much current into the batteries (dangerous, causes heating). That said, 24V into a 6s pack would take the cells to a safe 4.0V each.

Best to use a proper charger for the pack, separate the battery when using the 24V supply (maybe use a schottky diode, low fwd drop).
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#14
(11-10-2020, 07:08 AM)meanjeans Wrote: Regarding the 7S charger - I saw that in the title but I read somewhere that you want more than 24v to charge a 24v battery and I figured the BMS would cut off at the correct voltage.  Is a simple charger like the one I linked to appropriate to charge a battery pack like this via the BMS?

The terms "12V battery" and "24 battery" are very vague and can mean a lot of different things depending on context.  Best to more or less ignore that and look at the exact voltages instead.

To fully charge a LiIon cell, it usually takes a 4.2V source.  With a 6S arrangement, that's 25.2V total.  So you want to use a charger that outputs no more than 25.2V, like this one:
https://www.amazon.com/25-2V-Charger-cha...B085RYV377
If you had a 7S arrangement, the charger you now have with 29.4V output is just right.

Using a 7S charger to charge a 6S battery is... not ideal to say the least.  Should only be done in emergencies to give the battery a limited charge boost.  
Still not sure what went wrong in your case, but even in the best case the cells will paradoxically not get fully charged (maybe to 80%).

Note that these chargers may look like a standard wall plug AC/DC adapter, but the key difference is that the charger limits the output current to a set level (0.95A with yours).  If you tried charging the cells with a standard AC/DC adapter, a empty cell would likely suck several Amps of current, and overheat/overload something.
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