Is This Battery Pack for Real ($106) ??

George S.

Well-Known Member
Is This Battery for Real??

shorturl.at/suIOQ

I ordered this battery the end of March. It arrived last week, around May 13th. The package simply showed up with a DHL label on it. There was never any tracking. The cost was about what the ad states, plus sales tax. I guess Ali is enough of a monster that US states make sure they pay tax.

The battery pack contains 13 cells, but they are a larger 21700 cell, not the standard 18650. There are 13 cells in series and 3 in parallel. The claimed capacity of these relatively large cells is 5,000 mah, or 5 Amp. With 3 sets, this is a 48 volt and 15 AH battery. This works out to around 650 watt hours. Since 48 volts is a little high as an average useable voltage You shouldn’t just multiply amp hours by the nominal voltage. The watt hours will also depend on the low voltage cutoff point in the specific BMS you have. For the test I ran, the BMS cut at 42 volts, which is not the end of the battery, exactly. I use a watt hour meter, watt meter, and precision voltmeter on my bike. This is useful information to judge your battery as you ride.

In the initial rundown test, the battery was charged to 4.2 volts per cell, which is the normal standard for this type of Lithium cell. Most chargers will list 54.6 volts as the terminal voltage for a 48 volt pack. The rundown test used a 48v inverter connected to a 200 watt load. The test ran until the LVC on the inverter shut the inverter down, around 42 volts. The total watt hours at the end of the test was 626 watt hours. The voltage recovered to 42.5 volts or so. It’s hard to get useable amounts of power as the battery drops to 43 volts or so. Worrying about these garbage watts is not worth my efforts. If you were riding an ebike you would be drawing 200 watts, a useable amount of power, until the capacity was depleted. All of this is based on a few test cycles, which were consistent. This battery could supply 700 watts, full legal power, with a fresher charge. That’s all I tested. There are a lot of nuances to using a battery on an ebike. You need a cell that can supply the legal 750 watts. As the battery depletes, you need a cell that still provide useful voltages and amps to the end, or the practical end. These cells do the job.

Conclusions

1. The 21700 cell allows for a small pack and a very useful form factor. This pack, 600 wh, is the standard for more premium ebikes, but the new cell saves some space.

2. The cell that LK is using seems to be fine for standard ebike uses. It may not be a high power cell, but I don’t test for that.

3. There is no way to know how long the pack might last. There are safety measures that can be incorporated into any ebike pack, and it’s unlikely this pack is much more than robotic spot welded cells with a BMS. At some point I might cut the pack open but I doubt it. It’s a very nice looking pack. I do all my charging outside with solar.

4. There seems to be no way to trace where these cells may actually come from. Some say this 21700 is a re-wrap of Tesla cells, probably cells that graded below what Tesla wants. Tesla makes batteries in China. When people say not to buy Chinese cells, it’s meaningless. Is an LG cell made in China inferior to one made in Korea. As Joe Biden said, the Chinese want to dominate the EV battery market. The ebike market is a rounding error, in all this. China will develop this kind of cell and they will perfect the manufacturing. If this isn’t the breakthrough ‘Hundred Dollar Pack’ it doesn’t matter. You can pick up stuff from Battery Hookup or Jag35. You can buy LFP on Ebay. Certainly if you DIY and spot weld you can get a great cheap pack for low dollars.
20210514_120446.jpg20210514_114756.jpgPXL_20210520_183826702.MP.jpg
In some ways, China is laying down a marker with this pack. They are saying they can make a nice, perfectly usable ebike pack for $100. Maybe this pack shows what they will do or maybe it shows what they can do.

They can sell it directly. They did this with large prismatic LFP cells starting a year ago. Their position has only gotten stronger. That was EVE, and now EVE is supplying to Tesla.


 
Last edited:

Bitmugger

Active Member
Region
Canada
Great price! I have a different battery on order from a Chinese manufacturer. Would you update us after a month or two of use? I'd like to know if you experience any issues or suspect the cells are inferior at all.
 

harryS

Well-Known Member
Last year, I bought three 36V 10S2P 18650 shrinkwrapped packs from China. Advertised capacities were 7AH and 6AH, and I got 5.7AH and 4.5AH, which met my expectations. plus the packs have worked consistently for about a dozen cycles each.

This year I bought a 13S2P 21700 shrinkwrapped Laudation pack. Advertised as 10AH, it's about that much. My problem is it got unbalanced after three uses. One group came in at 3.0V when the rest were at full 4.2 V charge. I have an accurate 4.2V charger, so I recharged that group separately and got it to full charge, I figure the BMS was leaking that one group down. I'll know by the weekend if it does it again. Anyway, I ordered a better BMS. Did not file a ebay dispute with the seller. Figure it would be useless. He would probably say I shouldn't have opened the pack. Best I could expect is another crappy BMS.
 

George S.

Well-Known Member
I don’t know what to say about BMS boards. The old saying is “That’s another thing to break”. A lot of recycled stuff includes the note that the BMS is not usable. I’ve used packs with no BMS. In general, the basic nature of electricity balances out a pack. When they do go out of balance, it seems like maybe there is a bad BMS or maybe the cells in the pack won’t stay in balance as you discharge because there are different capacities across the strongs. I have a 4s LFP, big cells, used cells. One of the cells is 10 AH below the other three. If I charge for the weak cell, things are OK. I have balance leads on this pack. There are cheap ‘checkers’ if you have balance leads. That is the hobby market method, no BMS.
 

harryS

Well-Known Member
Last time I looked, the 48V Laudation pack was holding full charge. Perhaps the BMS is not leaking and it was owner abuse by me. The BMS says it's limited to 15 amps, but my wattmeter says I was pulling 25A out of it. Pulling too much current can also cause imbalance.

I intended to use this pack on a mild mannered 500W 48V TSDZ2 middrive, but I haven't put that together yet. So I was testing it on my 750W BBS02 mid drive. I'm surprised the BMS allowed 25A to flow,
 

HansTrio

New Member
Region
USA
I've generally been warned to stay away from anything but hard case batteries for ebike use.

I'm new to all this.

Are you guys putting these into a hard case?
 

indianajo

Well-Known Member
I've got 3 1/2 years & 7000 miles on a shrink wrap battery from Luna. I put a cage around it of aluminum angle SS machine screws & insulation to keep it warm. See on the front of the bike in the avatar. Never had a drop out.
 

Bitmugger

Active Member
Region
Canada
I've generally been warned to stay away from anything but hard case batteries for ebike use.

I'm new to all this.

Are you guys putting these into a hard case?

I don't have a lot of experience with batteries outside of a case but for my money a case is a good investment. I've dropped bikes over the years, I've got them wet, I've bashed them with garden tools and whatever I was carrying. I'd prefer my batteries have decent protection from some of these common scenarios. I would use a shrinkwrap pack but I'd mount it inside a box somehow, either something purchased like a pelican style box or an inexpensive Hailong case or something homemade. I've seen people do up ebikes with bricks or triangle batteries inside sheet metal, that seemed like a good way to do it.
 

Gionnirocket

Well-Known Member
Region
USA
City
Y. O.
Is This Battery for Real??

shorturl.at/suIOQ

I ordered this battery the end of March. It arrived last week, around May 13th. The package simply showed up with a DHL label on it. There was never any tracking. The cost was about what the ad states, plus sales tax. I guess Ali is enough of a monster that US states make sure they pay tax.

The battery pack contains 13 cells, but they are a larger 21700 cell, not the standard 18650. There are 13 cells in series and 3 in parallel. The claimed capacity of these relatively large cells is 5,000 mah, or 5 Amp. With 3 sets, this is a 48 volt and 15 AH battery. This works out to around 650 watt hours. Since 48 volts is a little high as an average useable voltage You shouldn’t just multiply amp hours by the nominal voltage. The watt hours will also depend on the low voltage cutoff point in the specific BMS you have. For the test I ran, the BMS cut at 42 volts, which is not the end of the battery, exactly. I use a watt hour meter, watt meter, and precision voltmeter on my bike. This is useful information to judge your battery as you ride.

In the initial rundown test, the battery was charged to 4.2 volts per cell, which is the normal standard for this type of Lithium cell. Most chargers will list 54.6 volts as the terminal voltage for a 48 volt pack. The rundown test used a 48v inverter connected to a 200 watt load. The test ran until the LVC on the inverter shut the inverter down, around 42 volts. The total watt hours at the end of the test was 626 watt hours. The voltage recovered to 42.5 volts or so. It’s hard to get useable amounts of power as the battery drops to 43 volts or so. Worrying about these garbage watts is not worth my efforts. If you were riding an ebike you would be drawing 200 watts, a useable amount of power, until the capacity was depleted. All of this is based on a few test cycles, which were consistent. This battery could supply 700 watts, full legal power, with a fresher charge. That’s all I tested. There are a lot of nuances to using a battery on an ebike. You need a cell that can supply the legal 750 watts. As the battery depletes, you need a cell that still provide useful voltages and amps to the end, or the practical end. These cells do the job.

Conclusions

1. The 21700 cell allows for a small pack and a very useful form factor. This pack, 600 wh, is the standard for more premium ebikes, but the new cell saves some space.

2. The cell that LK is using seems to be fine for standard ebike uses. It may not be a high power cell, but I don’t test for that.

3. There is no way to know how long the pack might last. There are safety measures that can be incorporated into any ebike pack, and it’s unlikely this pack is much more than robotic spot welded cells with a BMS. At some point I might cut the pack open but I doubt it. It’s a very nice looking pack. I do all my charging outside with solar.

4. There seems to be no way to trace where these cells may actually come from. Some say this 21700 is a re-wrap of Tesla cells, probably cells that graded below what Tesla wants. Tesla makes batteries in China. When people say not to buy Chinese cells, it’s meaningless. Is an LG cell made in China inferior to one made in Korea. As Joe Biden said, the Chinese want to dominate the EV battery market. The ebike market is a rounding error, in all this. China will develop this kind of cell and they will perfect the manufacturing. If this isn’t the breakthrough ‘Hundred Dollar Pack’ it doesn’t matter. You can pick up stuff from Battery Hookup or Jag35. You can buy LFP on Ebay. Certainly if you DIY and spot weld you can get a great cheap pack for low dollars.
View attachment 88193View attachment 88194View attachment 88195
In some ways, China is laying down a marker with this pack. They are saying they can make a nice, perfectly usable ebike pack for $100. Maybe this pack shows what they will do or maybe it shows what they can do.

They can sell it directly. They did this with large prismatic LFP cells starting a year ago. Their position has only gotten stronger. That was EVE, and now EVE is supplying to Tesla.


If you get a chance... Can you measure the battery size accurately?
Danke
 

harryS

Well-Known Member
I've generally been warned to stay away from anything but hard case batteries for ebike use.
Are you guys putting these into a hard case?
The first ones I got were hoverboard packs, and I wrapped them with rubber/foam padding and a second layer of shrink wrap. Then I put them in battery bags that have some padding. When I got into the rectangular packs, I continue to do this. I've seen my pannier bags rip open and spill batteries on the ground.

All these packs are small, usually 2x10 arrays, and the hoverboard packs are 3 cells high and 7 cells long, so I can store them inside some stacked hollow cinder blocks with a concrete paver on top.
 

HansTrio

New Member
Region
USA
The first ones I got were hoverboard packs, and I wrapped them with rubber/foam padding and a second layer of shrink wrap. Then I put them in battery bags that have some padding. When I got into the rectangular packs, I continue to do this. I've seen my pannier bags rip open and spill batteries on the ground.

All these packs are small, usually 2x10 arrays, and the hoverboard packs are 3 cells high and 7 cells long, so I can store them inside some stacked hollow cinder blocks with a concrete paver on top.

My "plan" is to use carbon fiber material I have left over from another project to build a custom hard pack with On/Off switch, vibration dampening, frame locks and custom mounts.
 

Gionnirocket

Well-Known Member
Region
USA
City
Y. O.
For shits ń giggles I'm going to give one of these a try as it's the only thing that I can find that'll fit in my triangle and I'm realizing that my rear rack battery is more than I need for a typical daily ride.... Plus I'm board and I need a diy project 🤣
If it's somewhat near its rated capacity, I'll be happy... If not, hopefully a dispute will end my way.
IMG_20210608_182047_362.JPG


The 30a continuous seems generous if not total bs.

That said I saw an interesting run of stories on NHK World News the other night on how China is really ramping up on batteries and EV's. I wonder if these packs are part of the introduction.
 

tomjasz

Well-Known Member
My "plan" is to use carbon fiber material I have left over from another project to build a custom hard pack with On/Off switch, vibration dampening, frame locks and custom mounts.
It’ll be hard to match the cost and quality of an EM3ev pack. Have fun.
 

EMGX

Well-Known Member
For shits ń giggles I'm going to give one of these a try as it's the only thing that I can find that'll fit in my triangle and I'm realizing that my rear rack battery is more than I need for a typical daily ride.... Plus I'm board and I need a diy project 🤣
If it's somewhat near its rated capacity, I'll be happy... If not, hopefully a dispute will end my way.
View attachment 89916

The 30a continuous seems generous if not total bs.

That said I saw an interesting run of stories on NHK World News the other night on how China is really ramping up on batteries and EV's. I wonder if these packs are part of the introduction.
I'm looking forward to your review. I have 3 batteries with Chinese cells that have been flawless with good range, so far. Another cheap battery advertised as having Samsung cells and it has been excellent as well. I'd like to try the battery you listed in a triangle bag also.
 

Gionnirocket

Well-Known Member
Region
USA
City
Y. O.
I'm looking forward to your review. I have 3 batteries with Chinese cells that have been flawless with good range, so far. Another cheap battery advertised as having Samsung cells and it has been excellent as well. I'd like to try the battery you listed in a triangle bag also.
I'll let you know what arrives... But it's going to be a while because of shipping restrictions and this thing will be on the proverbial slow boat.
I'm thinking 6 weeks at the earliest... Though it did get marked as shipped within 24 hours of purchase.
 

harryS

Well-Known Member
The 30a continuous seems generous if not total bs.
The Panasonic 22F's in my hoverboard packs, vintage 2016, were rated for 10A per cell. and in a 10S-2P config, do put out an honest 20A. Maybe the better generic 18650 chinese cells can match that 5 years later.

My 13S-2P 21700 pack has a BMS with a 15A rating, but the pack put out 25.5A into my 750W BBS02 motor. Voltage sag was 5.5 volts from 54.2V too. Not too good, but it was not intended to put put 25A. I think that's how it got unbalanced, because it's been anout 10 days since i rebalanced it, and it's fine.
 

tomjasz

Well-Known Member
Maybe the better generic 18650 chinese cells can match that 5 years later.
Cali eBike and California-eBike sold packs with generic Chinese cells. There are very good cells. but sorting the makers is a tuff nut to crack. I saw no more warranty issues with UPP generic cells over brand names. But IMO it's a crapshoot. Typically 36V and motors with 15A and under power gobbling is not an issue. But again, I didn't see any serious issues. Other than the usual UPP BS.

The scary part for me is those rewraps made to look like a brand name cell.

Here's a Luna BMS and a UPP.
71E3E766-9F37-4157-A894-51D3567683DC_1_105_c.jpeg
 

tomjasz

Well-Known Member
Panasonic 22F
i have a 20ah 22f pack from 2016. It rocked my 30A BBSHD at a solid 31mph. I like those old cheap cells with my BBS01A and B, 250W and 350W. I have too many batteries! And I'm willing to take risks the average DIY guys should avoid.