Tesla 3 2170 Panasonic or Samsung 50e (from BatteryEVO)

[eMark]

Battery Hookup just got in another supply of 2170 50e cells a couplle days ago, but quickly sold out ...
8 Samsung INR21700-50E 2170 4800mah ... Was going to buy 48 ...
"Sorry, We had an ebike company clear us out. Should have more in the future." (from BH)

So decided to purchase two of these 2170 modules from BatteryEVO. They say they are Tesla 3 2170 cells ...
Model 3 Cells 21700 24V lithium ion Battery 130 wh 5000 mAh XT60 .(could they actually be Sam 50e ?)
My first time ordering from Batteryevo.com ... appreciate any feedback (pro/con) ... free fshipping from CA to MN

Correction: Actually the two i ordered are these that i plan to parallel ...

Model 3 Cells 21700 36V lithium ion Battery 210wh 5000 mAh 10 cells XT60

Discover the power of Lithium Iron Phosphate LFP Batteries at BatteryEvo.com. Batteries for RV, Vans, Golf Carts, Solar and more!

batteryevo.com

 

[eMark]

BatteryEvo | eBay Stores

Welcome to my eBay Store. Please add me to your list of favorite sellers and visit often. Thank you for your business.

www.ebay.com

Still wotking just as if they were new cells. Originally purchased direct from EVO California ... apparently still available, but now via ebay.​

 

[eMark]

Shipped in original foam padded sturdy box (apparently unused overstock). Am using two connected in parallel (10s2p) for short ruas and as an emergency backup on my etrike. Ah capacity check from 41.50 resting volts to 30.00 cut-off voltage (8200 mAh) using this Atorch Discharger ... Amazon.com

"Class 3" title should have read "Model 3". No proof they were used in a Tesla 3 even though label says "Model 3".

The 10s sensing lead connector is not your typical 10s BMS pin spacing. Instead the connector is same as used on a 10s 1.2A balancing equalizer board (has closer pin spacing).

I don't use a BMS and so far no need to bottom balance parallel groups before charging ... so assume the cells are A-grade (parallel groups variance is no more than 6mV after discharge). No idea whether cells have a 10A, 15A, or 20A rating.

The downside is that these unused 10s1p (Model 3) 21700 batteries have been in storage (?3-5 years?) thus some loss in capacity (4100mAh instead of 5000mAH).

 

[docw009]

Looks like you bought these packs from ebay Did you set the Atorch up for 3-4A? Capacity tests are often done at 1A per cell, and from 4.2V to 2.5V, and they get a higher result.

For comparison, I got some 50E's last winter from Battery Hookup. They checked out around 4.9Ah tested bare in a Liitokala capacity tester, but dropped to 4.56AH with my Atorch at 1 amp per cell in a 13S-3P with BMS., That's 90%, which I think is realistic for these used cells.

Forgot what I paid, but when I include taking the cells out of the Battery Hookup batteries, and doing capacity tests on every one, I would just buy new 50E's for $4.75 from 18650batterystore.com if I were to do it again.

I might split one of your packs and mount it on both sides of the other to make a 10S-2P. Then wire in a BMS. I prefer having the safeguards. Then again, they may be safer left untouched.

 

[eMark]

Ordered two of those 36V 10s1p packs in May this year they were shipped free from BatteryEvo. It's only now that i noticed that BEvo uses ebay ... BatteryEvo | eBay Stores

Yes, my ATORCH discharge capacity test varied from 3.5A to 4.5A (never more than 140 watts) as more realistic to real-life than only !.5-2.5 amp discharge rate. In docware's "Ageing tests" he specified - "charge 1A to 4,1 V, 5 minutes wait, discharge 2,5A to 3,4 V, 5 minutes wait" I conducted three tests: First discharge test was on my paralleled 10s2p pack. The next two tests on each 10s1p battery.

When new it was good up to 160W. NOW my ATorch DL24p 180w load tester will shut down if discharging more than 142 watts (needs a bigger/better heat sink). No plans to modify as it serves my purpose AS IS. However, that may be why Amazon doesn't carry anymore, but does carry other similar brands. i really like all of its colorful readuout features. AliExpress lists it at $38.95 . i really like all of its colorful readuout features.

50E's don't fast long at BH. Haven't seen any 50E's available at BH since early May of '23, but i don't check every week (see my 1st post). That's why i ordered two 36v "Model 3 21700" packs directly from BatteryEvo.

I might split one of your packs and mount it on both sides of the other to make a 10S-2P. Then wire in a BMS. I prefer having the safeguards. Then again, they may be safer left untouched.

The first thing i did was parallel two "Model 3 - 21700" battery 10s1p packs end-to-end (best fit for rear Plano container) in their shipping cartoons using a XT60 Y-parallel cable. I'm my own best BMS having an accurate digital volt meter that reads to 3 decimal places (0.001v).I have no problem using the 10s sensing connector to keep tabs on the 10 parallel groups voltage variance after discharge. So far no need to bottom balance as voltage variance of the ten parallel groups is no more than 0.006 volts (6mV so far).

For someone just getting into 36v ebike or escooter without any soldering, spot welding tools or skill this would be an economical way.

Because the 21700 cells are labeled as "Model 3" there is no way of knowing if these unused battery packs are 5 years old or ten years old. So far they are performing (p-group balancing wise) AOK as A-grade cells. For my experimental curiosity only use for short errand runs or as backup reserve ... no complaints so far.

Impressed with battery fabrication and the original professional sturdy white cardboard shipping box with foam cushioning surrounding this 10s1p "Model 3" battery.

 

[docw009]

I've blown up two Atorch circuit boards, so I am used to moving the heat sink around to a new one, and adding more heat paste as needed. Maybe that's all you need. Sometimes, I blow a fan on the bottom too.

The first one blew up on first use, and I asked for a partial refund of $24 which aliexpress immediately granted. Then I bought the circuit board for $24. The next one lasted a long time, but I shorted out a trace on the circuit board. Bought another circuit board. Now I have it insulated.

 

[eMark]

One reviewer (2021) of the Atorch tried placing a Raspberry Pi heatsink on the diode, however the actual device has the heatsink side soldered to the PCB and uses the PCB as the heatsink, ("so I had little hope this would help. Indeed, it made no difference.")


Apparently this load tester is now sold under other brand name via Amazon (no longer sold as Atorch DL24p). For my capacity testing i don't need to discharge above 140watts so hopefully it will keep working.

Would you recommend this from AliExpress as an improved ATorch DLP24-plus upgrade ...

https://www.aliexpress.us/item/3256801272010454.html?gatewayAdapt=glo2usa4itemAdapt

 

[braincore]

Any updates on these Model 3 21700 5Ah cells? I was able to acquire 150 of them locally (someone's battery project that stalled) and am thinking about purchasing ~50 more from BatteryEvo.

 

[eMark]

Any updates on these Model 3 21700 5Ah cells? I was able to acquire 150 of them locally ( battery project that stalled) and am thinking about purchasing ~50 more from BatteryEvo.

Yes, they are suppose to be 5000mAh. However the capacity on all 4 of my 10s1p packs tested the same (4500mAh) using my Atorch Load tester ... https://m.media-amazon.com/images/I/816sLoUZVdL._AC_UL320_.jp

BatteryEvo now sells these 10s 36v Panasonic 21000 packs thru ebay. You could still call them to find out how many 10s packs they still have to sell via ebay ... Lot of 18 Model 3 Cells 2170 36V lithium ion Battery 210wh 5000 mAh 10 cell XT60 | eBay ... BateryEvo may sell these 10s1p packs in smaller quantities then what's llsted on ebay.

All 40 cells on my two 10s2p - 9Ah packs stayed balanced within 0.005-8V of each other (about 20 cycles so far at 90% charge / 80% discharge = 33V). Decided not to use any BMS - i'm my own BMS. On one pack i paralleled the two 10s sensing leads together by removing the two existing sensing wire connectors and adding a traditional RC balance lead connector (wider pin spacing).

Hopefully will attach photos of the two 10s2p - 9Ah packs later this week.

 

[DaLanMan]

There is a guy local to me that has a bunch of tesla cels, would you like me to shoot ya the contact info?

 

[braincore]

Yes, they are suppose to be 5000mAh. However the capacity on all 4 of my 10s1p packs tested the same (4500mAh) using my Atorch Load tester ... https://m.media-amazon.com/images/I/816sLoUZVdL._AC_UL320_.jp

Thanks for the info! Disappointing that you're seeing a maximum of 4500mAh, but not bad. You're getting approximately ~3150mAh per cell while staying in the 20% to 90% SoC range. If I see the same, I'll be expanding my pack size to accommodate.
https://m.media-amazon.com/images/I/816sLoUZVdL._AC_UL320_.jp

BatteryEvo now sells these 10s 36v Panasonic 21000 packs thru ebay. You could still call them to find out how many 10s packs they still have to sell via ebay ... Lot of 18 Model 3 Cells 2170 36V lithium ion Battery 210wh 5000 mAh 10 cell XT60 | eBay ... BateryEvo may sell these 10s1p packs in smaller quantities then what's llsted on ebay.

FWIW, I contacted BatteryEvo on ebay and they offered a ~10% discount on the 7S pack.

Hopefully will attach photos of the two 10s2p - 9Ah packs later this week.

Would like to see it!

 

[braincore]

There is a guy local to me that has a bunch of tesla cels, would you like me to shoot ya the contact info?

nocal or socal? Regardless, sure!

 

[DaLanMan]

San Jose, mid cal, sf bay

 

[eMark]

Thanks for the info! Disappointing that you're seeing a maximum of 4500mAh, but not bad. You're getting approximately ~3150mAh per cell while staying in the 20% to 90% SoC range. If I see the same, I'll be expanding my pack size to accommodate.
https://m.media-amazon.com/images/I/816sLoUZVdL._AC_UL320_.jp

9000mAh capacity (2 test runs on two different 10s2p 36v packs resulted in approx same 4500mAh (10s1p) capacity. Charged to 42.0 resting volts and discharged to 30.0v at 5amp discharge rate. I've tested new 30Q-6T 18650 cells resulting in 3000mAh ... so Atroch Load Tester seems to give accurate results Will do a Model 3 capacity test (10s2p tomorrow) from 42.0v (resting volts) to 30.0v discharge at 5amp discharge rate using Atorch Load Tester.

Will post the results Thursday with photos of my two 10s2p Tesla Model 3 packs. Its possible both the 7s and 10s packs from BatteryEvo may be at least 3-5 five years old and possibly cycled? Believe these Panasonic 21700 Model 3 cells may only have a 5amp MCD rating instead of 10A rating.

Here is a listing for Tesla Model X 21700 Panasonic (uncycled) cells $9.93 (4-9) to $7.31 (100+ quantity) ... Tesla Model-X 21700 5000mAh 10A Battery

 

[braincore]

Will post the results Thursday with photos of my two 10s2p Tesla Model 3 packs.

Looking forward to it.

Its possible both the 7s and 10s packs from BatteryEvo may be at least 3-5 five years old and possibly cycled? Believe these Panasonic 21700 Model 3 cells may only have a 5amp MCD rating instead of 10A rating.

BatteryEvo on ebay assured me that these cells have never been used. Interesting, if it's 5A MCD, do you know what a safe burst discharge would be?

 

[docw009]

I would like to stay below maximum continuous discharge, so 5A is restrictive. That's $4/cell with the 10% discount,

18650battery store has 50E's for $4.55, 9.8A MCD, and $4 if you buy 100+. My BBS02 runs off a 13x3 made with them. My Atorch says 13.7AH for the battery, or at the cell level, 4.5AH @ 1A down to 3V.

On the other hand, those 7S modules make for easy 14S brick batteries w/o welding.

 

[braincore]

Thanks for the advice. With a 72V system and a 1500W motor @ max, I'll be pulling ~21A continuous across 9 parallel cells, or ~2.3A/cell. 2x buffer seems reasonable.

I really do need to find a datasheet for these cells though like the one for the Model-X batteries.

 

[braincore]

This tester estimates the MCD of the Panasonic 2170A MC to be 10A and recommends keeping below 7A: Mooch

 

[eMark]

This tester estimates the MCD of the Panasonic 2170A MC to be 10A and recommends keeping below 7A: Mooch

That sounds in the Ball Park (Tesla Model 3 Panasonic 21700 5000mAh). Also agree thst they are uncycled considering the quality of the origianl shipping carton with plenty of protective foam.Those individual cartons are not on the cheap.

Ran another capacity test on my other two paralleled Tesla Model 3 (10s2P - SOC 42.1V, DOD 30.0V 10S2P = 8600mAh). Maintained discharge (as before) around 146-147W. during entire time except the last few minutes. Discharge amperage ranged from 3.5V to 4.5V.

Makes one wonder how Panasonic arrived at a capacity of 5000mAh. Still plan on posting a few photos some time 1st day of 2/24.

 

[Papa]

I have a box full of those Model 3 cells- 40 maybe 50, don't remember. Not used them or even built a pack. Most all are measuring 3.6V

 

[braincore]

I have a box full of those Model 3 cells- 40 maybe 50, don't remember. Not used them or even built a pack. Most all are measuring 3.6V

Yes, my box of 180 cells came at 3.6V as well. I think 3.67V. Let me know if you need someone to take those off your hands

 

[eMark]

Photo Typos: JST HX should be JST XH ...Too Much effort to go back and Photo edit. The 1-2 pin short shown on Photo 5 was my fault. BMS pin spacing too close when using DMM probes (as shown in Photo 1). When this happened the little wires were instantly fried (separated) so no damage to the cells. This is an experimental DIY prototype build so things happen (haste makes waste).

That's why i need to make up BMS connector to JST XH connector extension cables. Then will nor need to do the DIY intensive labor shown in Photo 4 on the other two 10s1p paralleled packs. Will still parallel the other 2 packs (as with this DIY build) using a X60 Y-cable as shown in Photo 6. With a DIY BMS to JST XH extension cable will not need to do the intensive labor and slow going safety shown in Photo 4.

Photo 3 shows the sturdy shipping cartons with good foam cushioning all around. For now when used to power my etrike it's stored in my Plano cargo container. Will replace shipping containers with 4" thin wall PVC pipe with foam cushioning and removable end caps.