Grin’s perspective of Ebike fires

[gromike]

How does one capacity test hundreds of cells?

 

[Hummina Shadeeba]

Seems a good resource for recycling batteries:

Recycling Center Search - Earth911.com

Find recycling centers and services in your neighborhood.

search.earth911.com

 

[floydr]

How does one capacity test hundreds of cells?

4 at a time with one of the 4 bay testers, I use Opus BT-3400 I have 4, one with external 26650 cell holders I use for A123 26650 cells. It takes time especially since you should only test the cells while you can keep a close eye on them. Not sure what @harrisonpatm uses. Use Charge only multi bay chargers To pre charge the cells prior to putting in the tester, making sure you remove the tested cells at the finish of testing cycle. I used the Charge/discharge/charge mode you can cut the time of a single a123 26650 2500mAh cell to ~2hours 45 minutes. I could test 12 cells in a bit over 8 hours. 18650's 2600mAh 16 cells at a time 48 cells in ~9 hours x many many days
You can also get the MegaCellcharger it does 16 18650's at a time.
Later floyd

 

[harrisonpatm]

I discussed the methods and equipment I personally use here and here (scroll down a few posts on each)

 

[Diggs]

How does one capacity test hundreds of cells?

...and to test and track capacity of entire packs I use one of these.

 

[docw009]

...and to test and track capacity of entire packs I use one of these.

I use the aliexpress atorch version at 1/2 the price. The glowing circle is a CPU cooling fan, The system can only dissipate 160 watts, so the max draw on a 48V pack is around 3 amps. That's a 3AH discharge rate, so it only takes 3-5 hours to rate battery capacity,

With the battery BMS holding LVC to 3V/cell instead of 2.5V/cell, you lose some of the rated capacity. Voltage sag in the battery contributes too, I usually see at best, 90% of rated cell capacity on the tester,



Real life capacity on an ebike further drops the useable capacity. I guess 80% is a good rule of thumb for a small battery. For example, a Sanyo GA pack was 90% on the tester and 83% on my bike. If you use massive 6P packs, you'll get better numbers,






.

 

[Diggs]

I use the aliexpress atorch version at 1/2 the price.

Exactly the one I have. I run a complete discharge with it on each pack at the end of each season and record the results so I can watch how each pack does over time. I run the same cells but by Panasonic (NCR18650GA) in 11p.

 

[Zambam]

Exactly the one I have. I run a complete discharge with it on each pack at the end of each season and record the results so I can watch how each pack does over time. I run the same cells but by Panasonic (NCR18650GA) in 11p.

Is this the one to get? https://www.aliexpress.us/item/2255...JoZGQ4D4&utparam-url=scene:search|query_from:

Says 2 to 200V. Does that mean you can load test any battery between 2 to 200V?

 

[Diggs]

Says 2 to 200V. Does that mean you can load test any battery between 2 to 200V?

Yes and yes. That's the one and tests from single cells up to the largest ebike battery pack. I also use it to test the 100ah
LiFePO4 batteries in our van.