These tests below only note the ESTIMATED ratings for these batteries at the time I tested them. Any battery that is not a genuine Samsung, Sony, Murata, LG, Panasonic, Molicel, or Sanyo can change at any time! This is one of the hazards of using “rewrapped” or batteries from other manufacturers so carefully research any battery you are considering using before purchasing.
Misusing or mishandling lithium-ion batteries can pose a SERIOUS RISK of personal injury or property damage. They are not meant to be used outside of a physically and electrically protected battery pack. Never exceed the battery’s current rating and keep the plastic wrap and top insulating ring in perfect condition. Use of any of these batteries is AT YOUR OWN RISK.
Testing batteries at their limits is dangerous and should never, ever, be attempted by anyone who has not thoroughly studied the dangers involved, understands the risks, has the proper equipment, and takes all appropriate safety precautions.
If the battery has only one current rating number, or if it only says "max", then I have to assume the battery is rated at that current level for any type of discharge, including continuous.
Test Results
This cell is available with a lot of different battery wraps and top contacts, all salvaged from Tesla Model 3 vehicles. While the ones I tested were good performers there is no way to know the condition of any of the cells you buy and you use them at your own risk.
Here’s how BigBattery prepares the cells:
This cell has recessed top contact that Tesla welds a cell-level fuse wire onto when they are used in a Tesla vehicle (see photos above). The companies that salvage these cells weld standard top contacts onto them and wrap them in various color wraps with different printing and ratings on them.
There has been concern that this recessed top contact could mean that these cells do not have the Current Interrupt Device (CID) that is in every cell made by the large manufacturers and hopefully every round cell we use. The CID is an important safety feature that shuts down the cell like a one-time circuit breaker if there is too much gas pressure building up inside due to misuse or mishandling. This can help keep the cell from bursting.
I took apart one of the cells I had and there appears to be a structure in the top contact structure of the cell (see the red arrows in the photos) that acts as a CID. But I cannot say for sure and I cannot guarantee that this cell will try to shut down if used too hard.
The cells I tested also have three tiny “stripes” in the bottom center that every Tesla Model 3 cell has and, AFAIK, no other cell has. I believe these marks are from the internal spot-welding of the tab of metal carrying current to the metal can from the spiral roll of materials inside the cell.
These Tesla cells equaled the performance of the Samsung 50E2/50E3 and Vapcell G50 (Samsung 50G rewrap). They performed a little better than the Molicel M50A and a lot better than the Samsung 50E and LG M50T.
The six cells I tested delivered from 4796mAh to 4888mAh and had a DC internal resistance ranging from 20.4mOhm to 22.9mOhm. This is not great consistency but these cells came from three different packs and their prior EV use (if any), storage time and conditions, and the quality of the top contact welding can affect their performance.
I estimate that these cells have a continuous current rating of about 10A to ensure decent cycle life and I rate them at 4800mAh. Like all of the ultra-high capacity 21700’s I recommend staying below about 7A (continuous or pulsed) to improve performance and minimize voltage sag.
Cells were donated for testing by Skyart (Battery Building Services by Skyart the skating duck) and MrDrunkenMobster (Duck Battery Systems | Custom PEV Batteries | Battery Building Supply). Thank you!
Continuous Current Discharge Graphs
Ratings and Performance Specs Graphic
I want to work for the vaping community full time! If you feel what I do is worth a couple dollars a month and you would like early access to battery availability, battery and charger testing and news, and a say in what I test, then please consider becoming a patron and supporting my testing efforts: Battery Mooch is creating battery and device tests | Patreon.
To see how other cells have tested check out this link: List of Battery Tests | E-Cigarette Forum
Misusing or mishandling lithium-ion batteries can pose a SERIOUS RISK of personal injury or property damage. They are not meant to be used outside of a physically and electrically protected battery pack. Never exceed the battery’s current rating and keep the plastic wrap and top insulating ring in perfect condition. Use of any of these batteries is AT YOUR OWN RISK.
Testing batteries at their limits is dangerous and should never, ever, be attempted by anyone who has not thoroughly studied the dangers involved, understands the risks, has the proper equipment, and takes all appropriate safety precautions.
If the battery has only one current rating number, or if it only says "max", then I have to assume the battery is rated at that current level for any type of discharge, including continuous.
Test Results
This cell is available with a lot of different battery wraps and top contacts, all salvaged from Tesla Model 3 vehicles. While the ones I tested were good performers there is no way to know the condition of any of the cells you buy and you use them at your own risk.
Here’s how BigBattery prepares the cells:
This cell has recessed top contact that Tesla welds a cell-level fuse wire onto when they are used in a Tesla vehicle (see photos above). The companies that salvage these cells weld standard top contacts onto them and wrap them in various color wraps with different printing and ratings on them.
There has been concern that this recessed top contact could mean that these cells do not have the Current Interrupt Device (CID) that is in every cell made by the large manufacturers and hopefully every round cell we use. The CID is an important safety feature that shuts down the cell like a one-time circuit breaker if there is too much gas pressure building up inside due to misuse or mishandling. This can help keep the cell from bursting.
I took apart one of the cells I had and there appears to be a structure in the top contact structure of the cell (see the red arrows in the photos) that acts as a CID. But I cannot say for sure and I cannot guarantee that this cell will try to shut down if used too hard.
The cells I tested also have three tiny “stripes” in the bottom center that every Tesla Model 3 cell has and, AFAIK, no other cell has. I believe these marks are from the internal spot-welding of the tab of metal carrying current to the metal can from the spiral roll of materials inside the cell.
These Tesla cells equaled the performance of the Samsung 50E2/50E3 and Vapcell G50 (Samsung 50G rewrap). They performed a little better than the Molicel M50A and a lot better than the Samsung 50E and LG M50T.
The six cells I tested delivered from 4796mAh to 4888mAh and had a DC internal resistance ranging from 20.4mOhm to 22.9mOhm. This is not great consistency but these cells came from three different packs and their prior EV use (if any), storage time and conditions, and the quality of the top contact welding can affect their performance.
I estimate that these cells have a continuous current rating of about 10A to ensure decent cycle life and I rate them at 4800mAh. Like all of the ultra-high capacity 21700’s I recommend staying below about 7A (continuous or pulsed) to improve performance and minimize voltage sag.
Cells were donated for testing by Skyart (Battery Building Services by Skyart the skating duck) and MrDrunkenMobster (Duck Battery Systems | Custom PEV Batteries | Battery Building Supply). Thank you!
Continuous Current Discharge Graphs
Ratings and Performance Specs Graphic
I want to work for the vaping community full time! If you feel what I do is worth a couple dollars a month and you would like early access to battery availability, battery and charger testing and news, and a say in what I test, then please consider becoming a patron and supporting my testing efforts: Battery Mooch is creating battery and device tests | Patreon.
To see how other cells have tested check out this link: List of Battery Tests | E-Cigarette Forum
