Charging with Daly BMS

[zks]

Hi all,

I’m new to charging Li-ion with a BMS. In the past I’ve always assumed a special charger is needed, but from my research it seems that to charge a 14S string of 3.7/4.2 Li-ion batteries (51.8/58.8 combined) with a 100A Daly BMS attached that I just need any power supply that can supply 58.8v (with current being non-critical - of course just affecting charge time), and the BMS will manage the actual charging.

I’m really just looking for confirmation of that as a generic power supply is much easier for me than finding one that does its own CC/CV management.

Thanks!

Z.

 

[John Frum]

The power supply must be constant current constant voltage.
Hiccup mode power supplies won't work.
The main difference between a cc/cv power supply and a charger is charge termination.
The BMS is not intended to be used for charge termination, especially at high current.

 

[zks]

The power supply must be constant current constant voltage.
Hiccup mode power supplies won't work.
The main difference between a cc/cv power supply and a charger is charge termination.
The BMS is not intended to be used for charge termination, especially at high current.

Thanks John! Just a follow up question… I thought the BMS will stop any charging from happening when one of the cells hits 4.2v? If so, doesn’t that terminate charging?

Basically I’m trying to find the easiest way to fully bench charge these two 51.8/58.8v battery packs I just got (comprised of 14 prismatic Samsung SDI Li-ion cells each, each with a Daly BMS on them). I don’t mind charging at, say, just 5A to get them to full charge. Once they are at full charge the MPPT solar charge controller will be used to manage them.

Thanks!

Z.

 

[zks]

Actually I just bought an 8A 58.8v CC/CV li-ion charger with OCP/OVP/OTP built in.

Thanks again for the help!

Z.

 

[John Frum]

Thanks John! Just a follow up question… I thought the BMS will stop any charging from happening when one of the cells hits 4.2v? If so, doesn’t that terminate charging?

Make sure of the actual trigger points.
Some Daly BMSs have trigger points outside what I would consider safe.
If the trigger points are set properly the BMS should disconnect when the first cell hits the trigger voltage.
But the BMS is meant to be a backup parachute not a charge controller.