View Single Post
Old 02-24-2014, 12:55 AM   #20 (permalink)
retepsnikrep
EcoModding Lurker
 
Join Date: Jul 2010
Location: UK
Posts: 73
Thanks: 0
Thanked 37 Times in 23 Posts
Balancing

I top balance with all my Lithium systems because

1) It's a bit easier technically and I understand it.
2) It ensures all the cells reach 100% soc at least when first fitted.

I monitor the voltage of every cell and keep them in a safe operating voltage window when driving/charging.

As soon as the weakest cell starts falling to my cutoff voltage threshold then I declare the pack exhausted. And vice versa when charging.

I don't top balance every cell every day to 100%.
As soon as the first cell reaches full when grid charging I declare the pack full.
I actively balance once a week or so and the cells tend to keep well in sync.

Been doing it since 2003 with my own BMS, several lithium packs and conversions.

To make a fuel gauge I fully charged my pack, set an Ah counter going and then drove it normally until it was exhausted. I then used that Ah figure -5% and calibrated it to a 0-100% range display. Works for me.
  Reply With Quote