I bought a 36V 20AH pack from seller dy-power, includes BMS. So far so good, it measure out fine, meets AH spec at a 0.5A rate (that's all the power resistors I have), and charges fine. It's your basic duct tape pack for <$30/AH.
At $578 delivered, that's $28.90/AH which was the best I could find at the time I was looking. You also have to consider they do NOT include a charger. I bought one from ping for $52 delivered so my total cost per AH is $31.50. That's still a good price per AH I think.
Using Dewalt 36V batteries for example, which I would dearly love to, are closer to $100/AH.
I realize that AH only tells part of the story, and it is an important consideration. The continuous discharge rate is also important, particularly for high power applications. The pack I bought from dy-power is 1.5C or 30A continuous discharge which is over 1KW. Since I'm using a 600W motor and a 30A controller, the pack will meet my needs.
It has independent discharge and charge wires, 4 total. Both + (red) wires go directly into the pack, both - (black) wires go into the BMS. Charge wires look to be around 18 gauge, discharge looks to be about 12 gauge.
Seller states the BMS protects from both over charge and over discharge.
Last edited by misslexi; 09-24-08 at 03:21 PM.