48v 30ah Battery....

[FLBikeDude]

Has anyone bought a battery from these guys before?

http://www.ebay.com/itm/261571374811

They seemed to have a decent price for an over (supposedly) 1400wh pack. So I purchased one and so far it's running pretty good..
Before I hooked it up to my controller, I put it on the charger and let it charge for four days straight.
I have run it about 10 cycles so far, all of which were no peddling or just a tiny bit of peddling on startup, but not much.. The first 5, were short 5-6 mile rides and after each ride, I charged overnight.
(Unfortunately the BMS is located in the battery pack. I don't want to open it up until I really have to.).
Each successive ride after those initial 5 were longer and longer (with overnight charges in between) until I finally did a 45 mile ride yesterday. (Voltage at the end was 51.2v ~3.2v per cell - 16 cell pack - tested with my multimeter). I don't have a wattmeter yet, to check AH usage yet.

I'm planning on running it to LVC today to see my max mileage.
(After I go 45 Miles, I'll check the voltage every few miles - The LEDs on my throttle - Green,yellow,red - are good indicators of general voltage. The green one goes dim when I get down below 50 V. So if that one goes dim while I'm riding on though I'm close to LVC.)
And no, I won't be very far from an outlet to charge, IF I don't want to pedal back home.
I'm expecting between 54 and 58 miles total distance before LVC kicks in, given my average of 25 W-hours per mile when I had a wattmeter to test my controller a few months back.

Comments? Comments? Queries?

Curious to know if anybody else had purchased a battery from them and their experience with that battery.

 

[dogman dan]

Well, it doesn't appear to be a V power HK pack. It's weight seems to indicate its made with pouch cells. One would assume they are not more than 2c cells.

The low c rate of the cells shouldn't matter too much for you, not with 30 ah. You can hit that thing with 30 amps and still be at 1c.

 

[FLBikeDude]

Well my best case scenario was tested yesterday..
Pedal on startup every time (Up till about 8mph), slow progression of speed up to 18 mph meaning no WOT and little to no wind against me. I CAN do up to 26-28mph, but for this test I wanted best case.
71 Miles total! At LVC.

Soon will test worst case with no pedaling onstartup and good progression of speed up to 20-22mph.

 

[FLBikeDude]

So today I went for worst-case scenario.
Very very little to almost no pedaling on start up. - I only pedaled a little on startup when the battery gauge's full/green light started "fading" towards the last 3 Miles before I hit LVC.
Constantly did 20 mph on average. Between 18 and 22 mph. A lot of stop lights.
Had my son hold on to the back of the bike while he was on a skateboard for 5 miles.
Went over about three small overpasses that went over I-95. (South Florida is very flat)
Wind against me about 85% of the time.
Battery hit LVC at exactly 48 V which is an average of 3 V per cell - I can't check cell level because BMS is under shrink wrap. (BTW, the BMS does NOT get hot (or even warm) under discharge..)
Battery again 48v 30ah
Controller 48v 20a
Motor - HBS 48v1000w - Goldenmotor.

Total miles?
51.327 Miles

Not too shabby.... When I get a Wattmeter, I'll have more technical specs to describe better the
wh, ah, etc usage.

 

[imorton]

Nice reporting…

I see that you got between 20wh/m at the best, and @ 30wh/m in the worst case scenario…

IAN.

 

[DAND214]

Did you have a voltmeter on the battery when it shut down or read after you stpped?
48v is rather high for LVC, since LVC is stated like 34 I think I read.

Gonna take some long time to get all cells balanced.

It's good to hear that there are some low priced sellers out there. But better yet IN THE STATES!

Dan

 

[dnmun]

i saw he is using the ping signalab and uses only 2 mosfets on the low current versions. that is getting pretty cheap imo.

but the packs appear to be made from individual pouches of the capacity mentioned. if you look at the dimensions you can see that each capacity has different sized pouches so he is not wiring it by putting numerous 5Ah pouches in parallel like li ping and sun-thing guy does.

so i think each size of battery uses a different size pouch, none of them as small as the ping or sun-thing 5Ah pouches which are 100mm wide.

but if the 48V20Ah pack is a little over 300mm long then each pouch is about 1/2" thick so it will have a low C discharge rate to get all that charge outa one tab. the current through one tab is what limits the C rate. so that may be why he hit LVC early if there is a lotta sag at the 2C max rate he appears to be climbing up to.

but obviously the pack is way outa balance since it is a new pack by all appearances. so it could be just the one channel. at least he knows the BMS functions and saved the pack.

 

[FLBikeDude]

I couldn't read the voltage when it cut off at LVC.
I had to plug in the charger for about 5 seconds until the BMS output mosfets turned back on.
That is when I read the voltage...
My bike (and me) weigh over 300lbs so the Wh usage is about right.
And even if they are "way out of balance" a 50-70 mile range is good enough for now.
I don't want to open up the pack to get to the BMS until I HAVE to.
My controller is 20 A max so there's no way I'm even getting even close to 1C.
Max amperage would be .66C
I have the 30 Ah pack. I would guess my average usage is somewhere in the 10 to 12 amp range. That would be about .33c

 

[FLBikeDude]

My controller is 20 A max so there's no way I'm even getting even close to 1C.
Max amperage would be .66C
I have the 30 Ah pack. I would guess my average usage is somewhere in the 10 to 12 amp range. That would be about .33c

 

[FLBikeDude]

Well today I did a run doing an average of 22 mph.
I got just under 60 miles distance before LVC.
I will let it charge for the next week without riding it to see if they really are out of balance and then check the range again with the same conditions.

 

[dogman dan]

Definitely working well for the use you are giving it. Nice find.

Lower c rate Lifepo4 may be old school nowdays, but it still works well if you carry enough of it to run it easy. With 30 ah, I wouldn't hesitate to run it as hard as the motor you have now will go.

Sweet to have that much range, I tend to carry 48v 25 ah all the time now. Even with higher c rate, I like less sag under load. Since the bike is a huge cargo carrier, I hardly notice the weight.

 

[FLBikeDude]

i saw he is using the ping signalab and uses only 2 mosfets on the low current versions. that is getting pretty cheap imo.

but the packs appear to be made from individual pouches of the capacity mentioned. if you look at the dimensions you can see that each capacity has different sized pouches so he is not wiring it by putting numerous 5Ah pouches in parallel like li ping and sun-thing guy does.

so i think each size of battery uses a different size pouch, none of them as small as the ping or sun-thing 5Ah pouches which are 100mm wide.

but if the 48V20Ah pack is a little over 300mm long then each pouch is about 1/2" thick so it will have a low C discharge rate to get all that charge outa one tab. the current through one tab is what limits the C rate. so that may be why he hit LVC early if there is a lotta sag at the 2C max rate he appears to be climbing up to.

but obviously the pack is way outa balance since it is a new pack by all appearances. so it could be just the one channel. at least he knows the BMS functions and saved the pack.

By the way, how did you find out or figure out what BMS he is using?
Also, like I said before I really don't want to remove the BMS out of the packaging until I really have to.
On a sidenote, I noticed that while charging the MOSFETs were really heating up I could feel the insane amount of heat coming off of that BMS. So, I took a 12v cooling fan from a broken 48v charger and hooked it up to blow air across the BMS while charging. It's definitely kept it way cooler. Now, instead of being so hot I could barely touch it to now being barely lukewarm. I saw another poster had an issue with his 48 V 10 amp hour battery that he got from the same seller who's had a problem with one of the cells blowing out, so I figured it might have been because the BMS was getting so hot that it burned into that cell, destroying it.