GBP Battery Co / 48V 20Ah Li-ion

[marty]

You sent them money, but have no idea what you ordered or how much you paid ??? Dude.....

Can not tell what I paid. Top secret. If I did tell you. I would have to kill you. Can not tell what I will sell batteries for, because I have no batteries to sell. You get nothing for nothing at VoltEV.com OK.... Dude.....

[marty]

Got battery many months ago. Its been sitting on the floor. One of my many unfinished projects. OK.... Here's the report. Size and weight is almost exactly as stated. [See first post this topic] Came wrapped with some sticky brown cardboard. Think Xyster could do better with duct tape. See pictures.

[marty]

TESTING! Fabrication guy is almost done with battery tester. 100W 50 Ohm resistor, and 55V bulb mounted to a sheet of aluminum.

Look at picture of the BMS. There are 4 gismos in it. See picture of gismo. [Gismo pictured is not mine] Did not take BMS apart because if it's not broke don't fix it. Rest of electronic stuff in BMS is covered with black goo.

Got questions about voltages? After charging, voltage of 13 cells should be about 54.6V Right? According to http://www.gbp-battery.com web site, each cell should be 4.2V at full charge. 4.2 x 13 = 54.6 Will BMS shut down when a certain low voltage is reached? What voltage would that be?

Will monitor voltage with meter while battery is discharging. Anything else I should know?

[xyster]

...Came wrapped with some sticky brown cardboard. Think Xyster could do better with duct tape. See pictures.

I'll put my duct tape up against anybody, anywhere, anytime. Oh, that sounds a little weird....

Nice antique scale, btw.

Will monitor voltage with meter while battery is discharging. Anything else I should know?

Don't trust the BMS's cut-off. If it doesn't cut-out before 48.1v -- 3.7v/cell -- stop the power there. Depending on the BMS cell balance function, some cells could be substantially lower, and well into permanent damage territory by that point.

[marty]

Battery tester is done. We testing. Battery load tester is real HOT! [portable battery powered oven?] Don't try this at home kids. After charging voltage was 54.8V It's slowly going down now.

Don't trust the BMS's cut-off. If it doesn't cut-out before 48.1v -- 3.7v/cell -- stop the power there. Depending on the BMS cell balance function, some cells could be substantially lower, and well into permanent damage territory by that point.

Sorry Xyster, I would rather sleep then watch battery discharge. Do have voltmeter hooked up. Keep looking at voltage. Don't have time for battery baby sitting. According to chart on page 1 of this topic. BMS cut off is around 2.75V per cell or about 35 volts for 13 cells. Will hope and pray that it does stop around 35V ?

For those of you who care? Here is parts list for battery tester. WARNING! it gets HOT!

3/16" x 12" x 12" aluminum sheet
RESISTOR Alcol 100W 50 Ohm, part # HS100 50R 1%
LAMP HOLDER SPC Technology, Miniature Bayonet socket, part # 21722
BULB SPC Technology, Miniature Bayonet lamp 55V, part # 1835
FUSE HOLDER Cooper Bussmann, 1/4 x 1-1/4, Panel Mount, part # S-8002-1-R
FUSE Cooper Bussmann, 5A, 1/4 x 1-1/4, part # AGC-5
CABLE CLAMP Thomas & Betts, Catamount, .125 Diameter, part # N4NY-002-0-M
FEET Plastic Bumper, 5/8" McMaster-Carr part # 9405K18

Anyone wana buy 98 small cable clamps, or 96 plastic bumper feet? Will give you good deal!

[TylerDurden]

...Don't have time for battery baby sitting.

Too bad... it's a great opportunity to learn more about your pack.

[magudaman]

Isn't that 50 ohm resistor only consuming something like 50 watts? You could do low load testing with the CBA and get a nice curved graph with a shut off that won't be so hard on your batteries.

[xyster]

Don't trust the BMS's cut-off. If it doesn't cut-out before 48.1v -- 3.7v/cell -- stop the power there. Depending on the BMS cell balance function, some cells could be substantially lower, and well into permanent damage territory by that point.

Sorry Xyster, I would rather sleep then watch battery discharge. Do have voltmeter hooked up. Keep looking at voltage. Don't have time for battery baby sitting. According to chart on page 1 of this topic. BMS cut off is around 2.75V per cell or about 35 volts for 13 cells. Will hope and pray that it does stop around 35V ?

No skin off my nose, but if there's a problem with the BMS as is not uncommon, you'll pay through the nose later for not taking a second or two while riding to check the voltmeter.

[marty]

Testing is done. Next step is go buy a bicycle.

Isn't that 50 ohm resistor only consuming something like 50 watts?

Don't know? My electrical design guy tell me to buy 100W 50 Ohm Resistor. Aluminum plate got hot. Think it was hot enough to cook a egg slowly? Test went for 12 to 20 hours? Don't know exact time, because I went to sleep. Could have cooked enough eggs to feed a small army?

You could do low load testing with the CBA and get a nice curved graph with a shut off that won't be so hard on your batteries.

What's a CBA? Computer Battery Analyzer?

No skin off my nose, but if there's a problem with the BMS as is not uncommon,...

Voltage went to 0V According to what I read on this forum, discharging lithium batteries to 0V is bad Luckily.... I don't believe everything I read. Did I do Permanente damage? Hope not. From now on I will not call that electronic thing with multi colored wires on the side of battery a BMS. Suspect it does regulate charging?

After testing / killing? battery voltage was 0V. Charged it up. Red and Green lights on charger worked fine. Total voltage is now 53.7V Measured each cell.
8 at 4.2V
3 at 4.1V
2 at 4.0V

Hope to go bicycle shopping this week.

[magudaman]

If it read a flat zero then the BMS may have shut it down. There most likely would still be a little voltage if you had destroyed your pack like you said. Draining a lithium battery to zero pretty much destroys it, so I would hope you didn't really do that either. The BMS will usually cut the power off way before that point to prevent damage. You really should watch the pack on a first discharge. But I guess if you you really don't have time for that then you could be out making money that you would need to replace that pack if the BMS didn't work.

Yes the CBA is computer battery analyzer and can be purchased here: http://www.westmountainradio.com

[marty]

If it read a flat zero then the BMS may have shut it down.

Duh.... Now I understand. Thanks for explaining that to me. Do wish I knew the voltage when BMS shut down? CBA would be nice.

[Yesa-battery]

Hello,marty,

48V 20AH li-ion battery (13 cells) ,

48/13=3.7V

So the battery is not LiFePO4 , LiFePO4 cell should be 3.2V , maybe LiMn2O4. Just guess, not sure.

[marty]

Hello Mr William, Yesa-battery Man,
You can call my battery LiMn2O414789632?????? if you want? Just to let it be known. I call my battery, Marty-Battery. Model Li1. My battery is number one!

Would like to see some pictures of your battery. Naked please. Tear off that shrink wrap! I show you mine. Now show me yours. Please start a new topic. Click on button that say [new topic] Tell us all about your batteries? I like to look at pictures. Do you have 48V 20Ahr? What is size weight? What is price? Got pictures of charger? Got any colorful graphs?

[fechter]

Yes, please show us the insides.
Show us the factory where they are made.
Show us test results
Tell us how much they cost and what sizes are available.

and on and on....

You can post pictures on the forum by using the browse and Add Attachment buttons under the text box.

[marty]

Yes, please show us the insides.
Show us the factory where they are made.
Show us test results
Tell us how much they cost and what sizes are available.

and on and on....

You can post pictures on the forum by using the browse and Add Attachment buttons under the text box.

Here's your pictures Fechter. Only took me 5 years to upload these. I've been busy. Sorry about that.

48V_20Ah 001_side.jpg (63.81 KiB) Viewed 263 times

48V_20Ah 002_top.jpg (78.1 KiB) Viewed 263 times

48V_20Ah 003_ruler.jpg (55.86 KiB) Viewed 263 times

4

48V_20Ah_bms.jpg (65.25 KiB) Viewed 263 times

48V_20Ah 004_scale.1.jpg (58.47 KiB) Viewed 263 times

6

48V_20Ah 005_scale.2.jpg (52.03 KiB) Viewed 263 times

48V_20Ah 006_charger.1.jpg (51.15 KiB) Viewed 263 times

48V_20Ah 007_charger.2.jpg (65.1 KiB) Viewed 263 times

[fechter]

Well, then you should have long term test results by now

I love the rusty scale!

[cwah]

My battery (Limn2O4 or Li(NiCoMn)O2) has lost 40% of its capacity in 6 months.

Have done around 70-100 cycles on it.

[nechaus]

Thats some nice old looking scales.

[Kin]

My battery (Limn2O4 or Li(NiCoMn)O2) has lost 40% of its capacity in 6 months.

Have done around 70-100 cycles on it.

That's insanely high. What C rating are you running it at? Does the pack get hot after using it?

[cwah]

Yeah, that's really bad. I'm only running at 1.2C rating continuous.

Not very high.. Very often I leave my bike outside, on the cold (0 Celcius outside) and the heat (25 Celcius outside). Maybe sometime the sunlight damaged the batteries as the decay is extremely fast over 50 Celcius. I can't tell thought.

[Hugues]

I compared the 100ah type of GBP to a Winston cell,
Winston comes out much better in term of energy density in weight and volume.

[Ypedal]

I got 2 of the 36v 20ah packs made from these cells just about the same time Marty got his ( a few months before ) .

I just ran a capacity test on one of the 2 packs ( I've let a local friend use it for the last 2 years. )

I fully charged the pack, cell by cell to 4.20v via the ballance leads. let sit overnight..

cell no.9 of 10 is bad from day 1.. had a big dent in it on arrival.. falconev was not honoring any warranties so it's been used as is since..

I got 8.0 ah before cell.9 dropped to 3.1v, all other cells holding 3.6v ..

Marty, are you using that pack ?

[marty]

Bought this battery for Electric Bike Project #2. This is one of my unfinished projects. Hope to complete it real soon.

Back in 2007 I charged and discharged a few times. After that battery just sat. Now the charger that came with battery will not charge. I charged each cell separately with Hyperion EOS 1420i NET3 Charger. Cell number 8 is dead and swollen. Cell number 7 is swollen a little on the bottom.

I need to buy 2 cells. Ypedal, do you got any cells for sale?

Test with CBA III - Computerized Battery Analyzer
Attached please see PDF file 48V_20Ah_test1

48V_20Ah_test1.pdf

(74.17 KiB) Downloaded 7 times

cel01:
Description: 1 Li-ion cell, 20.0 Ah @ 20.00A
Started At: 4/15/2012 9:44 PM
Discharge Rate: 20.00 A
Starting Voltage: 4.00 V
Ending Voltage: 2.80 V
Total Time (hh:mm:ss): 00:31:06
Tested Capacity: 10.423 Ah

cel02:
Description: 1 Li-ion cell, 20.0 Ah @ 20.00A
Started At: 4/15/2012 10:34 PM
Discharge Rate: 20.00 A
Starting Voltage: 4.00 V
Ending Voltage: 2.80 V
Total Time (hh:mm:ss): 00:40:47
Tested Capacity: 13.665 Ah

cel03:
Description: 1 Li-ion cell, 20.0 Ah @ 20.00A
Started At: 4/16/2012 7:49 AM
Discharge Rate: 20.00 A
Starting Voltage: 4.00 V
Ending Voltage: 2.80 V
Total Time (hh:mm:ss): 00:37:04
Tested Capacity: 12.419 Ah

cel04:
Description: 1 Li-ion cell, 20.0 Ah @ 20.00A
Started At: 4/16/2012 8:40 AM
Discharge Rate: 20.00 A
Starting Voltage: 4.02 V
Ending Voltage: 2.80 V
Total Time (hh:mm:ss): 00:39:54
Tested Capacity: 13.369 Ah

cel05:
Description: 1 Li-ion cell, 20.0 Ah @ 20.00A
Started At: 4/16/2012 9:39 AM
Discharge Rate: 20.00 A
Starting Voltage: 4.00 V
Ending Voltage: 2.80 V
Total Time (hh:mm:ss): 00:35:20
Tested Capacity: 11.837 Ah

cel06:
Description: 1 Li-ion cell, 20.0 Ah @ 20.00A
Started At: 4/16/2012 5:57 PM
Discharge Rate: 20.00 A
Starting Voltage: 3.97 V
Ending Voltage: 2.80 V
Total Time (hh:mm:ss): 00:34:23
Tested Capacity: 11.519 Ah

cel07:
Description: 1 Li-ion cell, 20.0 Ah @ 20.00A
Started At: 4/16/2012 6:43 PM
Discharge Rate: 20.00 A
Starting Voltage: 4.02 V
Ending Voltage: 2.80 V
Total Time (hh:mm:ss): 00:27:54
Tested Capacity: 9.344 Ah

cel08:


cel09:
Description: 1 Li-ion cell, 20.0 Ah @ 20.00A
Started At: 4/16/2012 8:18 PM
Discharge Rate: 20.00 A
Starting Voltage: 3.99 V
Ending Voltage: 2.80 V
Total Time (hh:mm:ss): 00:31:22
Tested Capacity: 10.507 Ah

cel10:
Description: 1 Li-ion cell, 20.0 Ah @ 20.00A
Started At: 4/16/2012 8:57 PM
Discharge Rate: 20.00 A
Starting Voltage: 4.03 V
Ending Voltage: 2.80 V
Total Time (hh:mm:ss): 00:44:16
Tested Capacity: 14.833 Ah

cel11:
Description: 1 Li-ion cell, 20.0 Ah @ 20.00A
Started At: 4/17/2012 8:48 AM
Discharge Rate: 20.00 A
Starting Voltage: 4.01 V
Ending Voltage: 2.80 V
Total Time (hh:mm:ss): 00:34:38
Tested Capacity: 11.602 Ah

cel12:
Description: 1 Li-ion cell, 20.0 Ah @ 20.00A
Started At: 4/17/2012 9:34 AM
Discharge Rate: 20.00 A
Starting Voltage: 3.99 V
Ending Voltage: 2.80 V
Total Time (hh:mm:ss): 00:34:42
Tested Capacity: 11.625 Ah

cel13:
Description: 1 Li-ion cell, 20.0 Ah @ 20.00A
Started At: 4/18/2012 8:36 AM
Discharge Rate: 20.00 A
Starting Voltage: 4.01 V
Ending Voltage: 2.80 V
Total Time (hh:mm:ss): 00:39:18
Tested Capacity: 13.168 Ah

[heathyoung]

You could run it as a 12S, just need to determine if the BMS can be reconfigured. Most of the people running LIPO are counting 12S at 44V.

Your pack is also only as strong as the weakest cell - so you have a 10AH pack now.

[Ypedal]

Well.. i'm either making a 9S pack from mine if the rest will deliver 15+ ah, but if the remaining cells follow the capacity curve of yours and i cant get more than 13ah from a 20ah cell.. it's retirement time... if that's the case you can have anything i retire !!