joe tomten
100 W
I purchased this battery in order to do a conversion on my friends bike. He’s an avid cyclist/bike commuter, who wants his mtn. bike converted so he can pull his kid around on a tag-along on occasion. He wants a bike that works, and has little tolerance for messing around with a complex battery situation. Most of the folks whose bikes I've converted, or will convert, fit this description.
They are Ebike commuters, looking for transportation, and not for diy / hobby projects.
That is why I am looking for a state-side source of reasonably priced lifepo4 batteries that have a decent warranty and level of support. Other discussion about these batteries is found here: http://endless-sphere.com/forums/viewtopic.php?f=14&t=26399 .
The keling 48v15ahr lifepo4 battery:
Shipping wt. 21 lbs
Cost: $589.95 , Shipping: approx. $25
My cost was $450 delivered. So I got an approx $170 break off the regular price of this battery, in return for agreeing to do this review. { I think pricing has gone up since i bought the battery. }
Their website is here: http://www.goasisenergy.com/lifepo4_battery
Specs and dimensions are found there.
John has been selling these batteries on ebay for about a year and a half. Supposedly no returns in that period.
http://shop.ebay.com/kelinginc/m.html?_nkw=&_armrs=1&_from=&_ipg=&_trksid=p3686
Battery and charger voltages:
Mine came with 4 amp charger, with an alum. enclosure. Seems robust & is fan-cooled. Open circuit voltage: 58.7v. works fine on 100-120vac despite the red mark in the 220vac box.
So first thing we do is rip the thing open and hopefully avoid all of the balance wires. And underneath the shrink wrap and sticky paper covering we see :
A fiberglass cover, with foam standoffs, covering a bms,
Which sports - a massive heat sink. A sticker on the bms contains handwriting: "48v and 15ahr, but no obvious reference to bms amperage capacity. Three typical negative wires connected to the bms for battery, load, and charger.
Looking underneath - I can see a number of fets are bolted to the heat sink. I opt at this point to defer any further demolition, to keep the battery working long enough for testing.
Cells are tab-welded together in a 16s3p series configuration:
The cells are 32650’s - the same height as 26650’s, but fatter. Like a 1.25†(32mm) in width instead of the 26650’s 1†width.
(picture below shows both sizes next to each other)
Having torn apart a brand new, perfectly good finished battery, I now duct tape the battery back together, with a piece of ¼†plywood and foam underneath for protection when resting on the brake mount posts behind the seat of the townie/Xtracycle.
{ Oops, I completely forgot to test the voltage of each indiv. cell before wrapping it back up. Sorry.}
Ready now for some riding. It’s actually more secure than it looks - tied in there like that. {edit, Wrong! Still tied in there, but now more securely.}
First I rode around the block for a couple of miles, and then recharged. And from here forward I will ride it back and forth to work (7.5 – 8 miles & about 250watthrs usage each way), charging at either end like I typically do with my same sized 48v15ahr ping. As far as I can tell so far, it performs the same as a Ping, with a 20amp controller.
I have a 9-fet, 30 amp, controller on it's way from Lyen, and I'll give that a try as well.
They are Ebike commuters, looking for transportation, and not for diy / hobby projects.
That is why I am looking for a state-side source of reasonably priced lifepo4 batteries that have a decent warranty and level of support. Other discussion about these batteries is found here: http://endless-sphere.com/forums/viewtopic.php?f=14&t=26399 .
The keling 48v15ahr lifepo4 battery:
Shipping wt. 21 lbs
Cost: $589.95 , Shipping: approx. $25
My cost was $450 delivered. So I got an approx $170 break off the regular price of this battery, in return for agreeing to do this review. { I think pricing has gone up since i bought the battery. }
Their website is here: http://www.goasisenergy.com/lifepo4_battery
Specs and dimensions are found there.
John has been selling these batteries on ebay for about a year and a half. Supposedly no returns in that period.
http://shop.ebay.com/kelinginc/m.html?_nkw=&_armrs=1&_from=&_ipg=&_trksid=p3686
Battery and charger voltages:
Mine came with 4 amp charger, with an alum. enclosure. Seems robust & is fan-cooled. Open circuit voltage: 58.7v. works fine on 100-120vac despite the red mark in the 220vac box.
So first thing we do is rip the thing open and hopefully avoid all of the balance wires. And underneath the shrink wrap and sticky paper covering we see :
A fiberglass cover, with foam standoffs, covering a bms,
Which sports - a massive heat sink. A sticker on the bms contains handwriting: "48v and 15ahr, but no obvious reference to bms amperage capacity. Three typical negative wires connected to the bms for battery, load, and charger.
Looking underneath - I can see a number of fets are bolted to the heat sink. I opt at this point to defer any further demolition, to keep the battery working long enough for testing.
Cells are tab-welded together in a 16s3p series configuration:
The cells are 32650’s - the same height as 26650’s, but fatter. Like a 1.25†(32mm) in width instead of the 26650’s 1†width.
(picture below shows both sizes next to each other)
Having torn apart a brand new, perfectly good finished battery, I now duct tape the battery back together, with a piece of ¼†plywood and foam underneath for protection when resting on the brake mount posts behind the seat of the townie/Xtracycle.
{ Oops, I completely forgot to test the voltage of each indiv. cell before wrapping it back up. Sorry.}
Ready now for some riding. It’s actually more secure than it looks - tied in there like that. {edit, Wrong! Still tied in there, but now more securely.}
First I rode around the block for a couple of miles, and then recharged. And from here forward I will ride it back and forth to work (7.5 – 8 miles & about 250watthrs usage each way), charging at either end like I typically do with my same sized 48v15ahr ping. As far as I can tell so far, it performs the same as a Ping, with a 20amp controller.
I have a 9-fet, 30 amp, controller on it's way from Lyen, and I'll give that a try as well.
At least not sell like an ebay or other sellers website, click and buy.
