Charger help

[Matthewrobot]

Hi guys,

I recently built a 3s7p 12v battery with a bms.
Just to see if I could get my head round it.
I bought a sky rc charger to charge it but should have built in a charge indicator.

I’m looking for help on chargers with balance lead set ups. My next will be a 48v ebike battery, but what charger goes that big with balance leads?
Thanks in advance.

Matt

 

[From-A-To-B]

I came to the ebike hobby from the RC world. So I, like you, was accustomed to balance charging through the balance leads or bulk charging through the main leads and then using the balance leads to balance.

The ebike world handles this differently. While there are some hobby chargers with JST-XH ports that will accommodate batteries up to 10S, they are few and expensive. Instead, ebike packs are bulk-charged and the BMS keeps up with balancing in the final stages of the charge. Or, at least, it’s supposed to. Cheap BMS’s sometimes don’t balance or, really, protect the battery at all. You get what you pay for, YMMV.

Have a read around the battery sub-forum and bring yourself up to speed on how BMS’s work and your charger options. This is a great forum for self education— I believe in you!

To get you started, cheap 48V bulk chargers can be had for $40, many people like the $100 option from LunaCycle (myself included), and the CycleSatiator from GRIN is a rather well made high-budget option.

Congrats on your early success with your DIY pack. If you share pics, I’m sure people would love to laud you for your accomplishment and, if desired, offer advice to improve your next build.

Cheers!

 

[jas67]

If you use a BMS with balance leads, the charger does not need balance leads.

 

[Matthewrobot]

Thanks guys.
Looks like I’ll be doing some swatting up on the battery sub forum.