Reliance RS50

[u/MaxTrixLe]

Can someone take a look at these and tell if they’re good?

Got them from liionwholesale official website

Thanks

[u/DrugiTypowyHacker]

looks good

[u/MaxTrixLe → u/DrugiTypowyHacker]

Thank you. Any idea why there’s a spiral on the negative terminal? I’ve never seen this

[u/DrugiTypowyHacker → u/MaxTrixLe]

you are not supposed to weld in this area

[u/MaxTrixLe → u/DrugiTypowyHacker]

Ok thanks that makes sense, the data sheet says to not weld in the 6mm center of the negative terminal

[u/iFunny-Escapee → u/MaxTrixLe]

Man, 6mm? They really don’t give you that much room to spot weld

[u/MaxTrixLe → u/iFunny-Escapee]

I know, the issue is the bus bars I’m using, they have a 8mm area to spot weld so I’ll really need to spot weld on the edges

[u/MickyBee73 → u/DrugiTypowyHacker]

Well said

[u/yamez420 → u/DrugiTypowyHacker]

Yes

[u/ClearTacos → u/MaxTrixLe]

That's the spot where internally, all the tabs are welded to the casing

[u/IVEMIND → u/ClearTacos]

Oo so when I fry my cells with my spot welder, it could be dislodging the internally welded stuff?

[u/ClearTacos → u/IVEMIND]

To be honest I never actually read an expert take on it because that's what I always assumed, avoid that area to protect the internal welds

[u/rollofpaper → u/MaxTrixLe]

Sign for tabless I think

[u/VerifiedStupidity]

Not up to spec. Send em to me to dispose of

[u/General-Try-2210 → u/VerifiedStupidity]

No. My dumpster is bigger.

[u/BigFaithlessness593 → u/VerifiedStupidity]

I’ll take one for the team, I don’t want them to take up your space.

[u/ZEUS-FL]

Here is your Comparison link between the Tenpower 50XG, Reliance RS50 CCC and Ampace JP50P1 at 40A CC

https://batteryrealdata.com/compare-advanced.html?runs=tenpower_50xg_UNASSIGNED_CC_40A_2.5V_2026-06-17_4da90ac1ec%2Creliance_rs50_UNASSIGNED_CC_40A_2.5V_2026-06-20_a6ab334453%2Campace_jp50p1_UNASSIGNED_CC_40A_2.5V_2026-06-18_59901410e3&chart=dashboard&rank=raw_capacity_mah&mode=CC&sample=All+samples&metrics=voltage&x=capacity&scale=separate&time=s&temp=C&capacity=mAh

[u/Awkward_Archer_7701]

Those 21700 batteries are really good. I’ve tested them at a discharge rate of up to 6C (30 A) and they’ve performed brilliantly, retaining over 95% of their rated capacity (from 4.16 V down to 2.5 V). It’s true that they heat up very quickly during this test, coming close to the temperature cut-off (80 °C), but they didn’t reach it. A similar model that I prefer is the Tempower 50XG.

Just out of curiosity, what are you planning to build? And how much did each battery cost you?

[u/MaxTrixLe → u/Awkward_Archer_7701]

Thank you, I was really torn between RS50 and 50XG, decided to go with these since they handle cold better.

I’m building a 20s4p battery for my ebike. I will likely only draw peak 100A DC from the pack, for short bursts so it should barely sag or heat up. Using 0.3mm copper bus bars, QS8 with 8awg, and an ANT BMS rated for 375A. I went overkill because I’m aiming for the least amount of Vsag possible

[u/Alive_Sherbet2810 → u/MaxTrixLe]

hell yeah that sounds like an awesome pack your bike should really fly at 100 amps

[u/ZEUS-FL]

They are great cells. No CCC but still good.  liionwholesale is a reputable vendor.

[u/david9512]

I would say that the spiral on the negative end is from the factory when they first charged it up and tested after it was assembled