Is this battery good for me?

[bonoboca]

I have a BL36 and want to know if a 36V 20AH battery can fit (the kit originaly come with 3x 12V 12AH).

What is the advantage of higher AH ?
And is it a problem to install a higher voltage than the controler manage? What is the limit for a 36V controler?

Thank you

 

[swbluto]

If the bike originally came with 12AH, then 20AH would be even better. This has the effect of lowering your C-rate which would drop the voltage sag under load which'll give the perception of "increased performance": If this would be an upgrade from SLA to lithium, even more so. Don't know about the physical fit, though: Do you have measurements?

And it's a problem if the voltage of the battery exceeds the voltage rating of the components in the controller. Since you're using a wilderness, it's likely your 36volt controller has 60V mosfets(which stand the greatest chance of blowing while over-volting) and it might have a nominal rating of "24-36-48" which would physically allow 48v, but not 72v.

 

[bonoboca]

Thank you very much, I am lost when it come time to talk electricity. Here are specs http://tinyurl.com/6cpak5

 

[hippiehunter]

im not sure if anyone has had experiences with that seller or not. In the world of ebay batteries I think the sellers reputation is a point of great concern. You may want to go with someone more well known like pingping227. Its possible that daisypang is a great seller but with that kind of money in play.... I personally don't like to chance it. the other thing is, you can buy directly from ping and he will custom build to your specs usually.

 

[dogman dan]

I am running nearly the same motor, I have the bd36, on a 36v 20 ah battery bought from Li Ping. pingping227 on ebay. Its just about a perfect setup, right down to the fit in the battery bag. Ping is the only "duct tape battery" seller on ebay that has won the trust of this group. So the problem is how to win one of Pings auctions? No problem. Just email him at the address in his ad, and talk to him. Dealing direct may even get you a lower price, but normaly you will wait a bit longer for delivery. Essentially it's treated like a custom order. You will love the light weight, long ride, and no need to worry about charging right away if it's not convenient. No voltage sag means your battery will never be lower than about 40 volts, so it may even be a tad faster than the sla's and a lot faster at the end of a long ride. My bd motor is faster and more of a watt hog than yours, but I can still go 20 miles at 25mph with this battery. You should get further at 20 mph. Get the 20 ah sise, its worth it to not worry about running out, and the slower drain will make it last it's maximum. One thing about these batteries though, you will need to build some kind of box or something for some extra protection in a crash or just the bike falling off the stand. Even just some extra cardboard in the bag to cover the corners if they get bashed. I used an aluminum baking sheet cut and folded to box mine. Saved it when I crashed! I have 1200 trouble free miles on mine, unless you count a few times I didn't let it charge long enough.

 

[dogman dan]

Oh yeah, I forgot. Its well known that the bd36 and bl36 controllers work great on 48volts. So if you want to spring for the 48v 20ah Lifepo4, go for it. Should get you very close to 25mph. The motor can take more, but above 48v new controllers are needed. Once you have lifepo4, the lights on the throttle don't matter, I just use mine to see if I left it turned on.

 

[docnjoj]

Actually those lights tell u alot! When they go out at full throttle on a fresh charge, U know your battery sucks!
otherDoc

 

[dogman dan]

Now that I've ridden that far a few times, I can tell by the bike speed when the voltage sags from 43 to around 41, and know I have about 2 miles left before, Poof. Now I can also feel the difference between a hot motor controller shut off and the battery bms cutoff. The controller shutoff is real sudden, but the bms kinda goes pooof as the caps drain out. On a hot day , I won't get far enough to drain the battery.

 

[bonoboca]

Thank you dogman for all these informations :wink:
and thanks to swbluto for these usefull explanation.

 

[recumbent]

48 volt/20AH is a great power system for a bike, the extra AH rating also gives more torque it seems.

This will be my next choice of battery pack for my bike.