Are these Samsung batteries ok

[Maugerville]

I have built a Ebike for myself with plans for another for my wife. To keep cost down I opted for a cheaper battery that I will use later on my wife's bike. I have a BBSHD with a 48V supposedly 20Ah pack (pictures of the cells below) but when drawing ~peak 32A for spurts I have had it cut out. I plan on a BBS02 for my wife and at that time a larger 52V 23AH from a reputable seller for my bike.

What I want to know is this too many amps (~32) to draw from this battery for short spurts? Normally I only use 2-10A and can easily get 100km on PAS 2 or 3. I believe these are Samsung cells although they do not say.

 

[LewTwo]

See the URL: https://secondlifestorage.com/index.php?threads/samsung-icr18650-26c-cell-specifications.1782/

They seem to be missing some trailing digits in the battery label.
For that to be a 20 AHr pack there would need to be at least 8 cells in each string (more likely 7 as vendors tend to exaggerate). For 50 volts that would make it 14S7P or 98 cells. For For 47 volts that would make it 13S7P or 91 cells.

At 1C : 1x7x2.6 = 18.2 Amps
At 2C: 2x7x2.6 = 36.4 Amps

The source of cut-outs is more likely the BMS than the rather than the battery cells.
15, 20, 25 and 30 Amps are common cutoffs for BMS.

 

[john61ct]

So many pack sellers use the widespread counterfeits out there.

 

[E-HP]

I have built a Ebike for myself with plans for another for my wife. To keep cost down I opted for a cheaper battery that I will use later on my wife's bike. I have a BBSHD with a 48V supposedly 20Ah pack (pictures of the cells below) but when drawing ~peak 32A for spurts I have had it cut out. I plan on a BBS02 for my wife and at that time a larger 52V 23AH from a reputable seller. What I want to know is this too many amps to draw from this battery? Normally I only use 2-10A and can easily get 100km on PAS 2 or 3. I believe these are Samsung cells although they do not say.

IMG_0208.JPG
IMG_0209.JPG

I'm going to guess fake cells or a bait and switch, since the manufacturer can't do simple math. As LewTwo points out, the math works out to either an 18.2Ah pack, or 20.8Ah pack (using 2.6Ah cells, per the labeling), so either their 20Ah rating is based on another cell type (25R?) and they switched out for these, or they just threw in fake cells and guesstimated the capacity.

I'm guessing the cutout is due to voltage sag. Can you monitor the voltage?

 

[Maugerville]

I went for a 5 1/2 hour-100.56 KM ride yesterday and averaged 4.6wh/km (bike + me is a little over 300#. At the start the 48V battery was 54.5V and at the end of the ride was 47.6V. By rough calculations I believe it tells me the battery is between 19 and 20Ah. These stats were through eggrider and voltage was also checked with a voltmeter.

As far as voltage sag, when I was pushing the bike and the cut out occurred it was dropping voltage quite a bit but the battery was fresh and not going below 47V All I dad was power cycle the battery and it was fine. From what I read here I would say with them (builders) using counterfeit cells they probably used a cheap BMS as well.

All in all I am happy with the performance of the battery as it is on a on/off road touring bike so long as I can get a few years from the battery. I ONLY charge it to 100% just before a big ride and not let it drop below 25% It cost me $600 CDN with a rack and was here in 3 days but my next battery will be from EM 3 EV or I will build it.