12v 7amp vs. 12v 12amp battery.

[blippo]

What would your educated guess be given you were running an electric bike in the difference in total mileage you'd get in a charge between a bike, same motor, that had 3-12v, 7amp batteries vs. the same bike with 3- 12v, 12 amp batteries?

 

[TylerDurden]

If SLA: You'll likely get >50% more range, as the 7ah will sag into cuttoff much faster than 12ah will.

 

[blippo]

Thanks, I was testing the mileage now in winter for my Wilderness BL-36 kit. It had 3-12v,7amp SLA batteries. I got around 7 miles before the yellow light came on. That's with some pedaling, and I'm around 200lbs. So I just purchased 3- 12v 12amp SLA battieries I was going to try out.

 

[fechter]

Due to the Peukert effect, I'd guess a healthy set of 12's would be almost double the range of 7ah batts.

 

[blippo]

Another question, would you be able to run say, 3 batteries total , 2- 12v, 12amp batteries with 1- 12v, 7amp battery? Can you mix them like that ? Same volts but different Amps?

 

[fechter]

You could, but the 7 ah one will go dead first and will tend to get overcharged when charging. Generally that's a bad idea.

You can put different ah batteries in parallel no problem, but you need 36v. You could use two 12ah batts, and a pair of 7's in parallel (this makes 14ah) for the third. This would work better, but could still go unbalanced over time.

 

[blippo]

Great, thanks alot. That's good information

 

[Arbiker501]

Yeah i got the same BL 36.

I am getting about 10 miles before they go dead. However i am riding a light weight road bike with 700 wheels.

But for me they seem to loose speed in a mile or so. It would be nice if the 12 amp hour would hold some speed for you a while before they dropped off to nothing.

 

[blippo]

Arbiker501, in the summer I got a little more mileage while pedaling with the 7amp. Around 10-11 miles. When I purchased mine although they stated that it was the extended range, it came with the 7amp. And I had both the BL36 for the 700 tire and 26. It does a little better with the 26" wheel as far as speed goes.

 

[Arbiker501]

Yeah that may be it . I live in the south and my 10 miles has been with brand new batteries in 60 degree weather.

So that would add up .. Plus it is pretty flat

 

[blippo]

I had thoughts about trying that Chrystalyte motor next to see how that was, but I didn't know it would be worth the money