View Single Post
Old 06-28-2013, 08:39 AM   #16 (permalink)
Master EcoModder
Ryland's Avatar
Join Date: Jan 2008
Location: Western Wisconsin
Posts: 3,904

honda cb125 - '74 Honda CB 125 S1
90 day: 79.71 mpg (US)

green wedge - '81 Commuter Vehicles Inc. Commuti-Car

Blue VX - '93 Honda Civic VX
Thanks: 867
Thanked 433 Times in 353 Posts
I was pricing out Optima batteries and noticed that they cost about the same as my GBS brand lithium batteries for the same labeled capacity, the Optima batteries of course are heavy, rated for 300-500 cycles and can not handle as strong of discharge without seeing their capacity drop, my lithium batteries are tested to 2000 cycles with 70% capacity left at that time, that's discharging it fully every day for over 5 years and if you don't discharge as fully their capacity stays higher for more cycles.

All batteries need to be balanced, a pack that is never balanced will end up being a short lived pack, if you want to make a pack of lead acid batteries last as long as possible and perform at it's peek then put a battery management system on there! the other option of course with lead acid batteries is to manually balance the pack from time to time with a small charger over night, but without a good battery gauge that connects to each battery in the pack you have no idea what is going on with your pack or if anything is going wrong until you've caused damage.

I spent $1,800 on my 48v 100 amp hour lithium battery pack, it weighs 112 pounds, I then spent another $1,000 or so on the battery management system, LCD display and charger, all of the parts talk to each other so it can charge at a faster rate until a single cell starts to get full then it throttles back until the rest catch up, this feature cost a few $100 extra but it's well worth it.
If I wanted the same capacity with lead acid batteries the pack would weigh 520 pounds, take up 3 times as much space and last 500 cycles or less, I built my motorcycle up with 400 pounds of lead acid batteries and it was unsafe to ride, I have lithium batteries in it now and it's FUN and lighter then stock.
  Reply With Quote