New high capacity battery cells on the market.

[alcatraz]

Hey guys

I was browsing through the offers on the chinese mixed market Xianyu 闲鱼 (new+used) and I noticed three interesting newcomers.

Samsung 21700 53G cells. 5300mAh. I didn't see discharge rates on these but I'm guessing 2C so around 10-11A continuous. Tested capacity was a bit over 5300mAh (low current) Price 21CNY.

远东 Yuandong 18650 3800mAh cells. Tested capacity above 3800mAh. 2C discharge so 8A. The company product sheet even has a 18650-4000mAh cell on it but I haven't seen it actually for sale. Price 27CNY. 

Actually for sale is the 远东 Yuandong 21700-6000mAh. Tested capacity over 6100mAh. 2C discharge 12A. There's a 5500mAh model in the works too but no offer. The diameter is apparently 21.5mm so that's probably one way how they're cramming in more capacity. Price 42CNY. 

Just thought I'd give you guys a heads up that we're getting larger packs without added weight, in a near future. Availability and reliability are probably going to determine if we'll see these anytime soon.

Edited September 6, 2023 by alcatraz

[mhpr262]

13 minutes ago, alcatraz said:

Samsung 21700 53G cells. 5300mAh

They also have a higher voltage than the 50Es throughout the discharge cycle, from beginning to end, especially at high discharge currents. And what is even more interesting: they last more than twice as long as the 50Es. They retain more capacity after 1.000 full discharge cycles than the 50Es do after 500. Allegedly the Inmotion V14 Adventure uses the 50Gs.

[Paradox]

48 minutes ago, mhpr262 said:

Allegedly the Inmotion V14 Adventure uses the 50Gs

This is from eWheels:

 

[mhpr262]

I wonder when the first wheels featuring the 50S will turn up - 5.000mAh and can deliver 35A continuously. But the big wheels nowadays are so high voltage and have so many batteries in parallel that it may not even be very useful for those anymore.

They might make sense for a really powerful Mten4 or MCM5 sized fun  and stunt wheel with just two or three 20s packs in parallel.

[meepmeepmayer]

Capacities over 5000mAh! Nice! Bigger EUC batteries for free (meaning not heavier or physically bigger)!

I'm more excited about this than about high discharge cells, though high discharge cells are great because they allow lighter/smaller/cheaper wheels to still have proper performance to be useful and safe.

[alcatraz]

4 hours ago, mhpr262 said:

I wonder when the first wheels featuring the 50S will turn up - 5.000mAh and can deliver 35A continuously.

I'm guessing soon because they've dropped in price. New they're around 25CNY. Almost new 18CNY. The availability at these prices is probably still not good, but things are indeed happening.

I just ordered an Mten3 and I was thinking of building a 20S1P Samsung 50S 370Wh pack for it. It would drop its weight by over 1kg. 

Edited September 6, 2023 by alcatraz

[mhpr262]

Forgot to add that NanoGraf brought out a 4.000mAh 18650 cell in October last year:

NanoGraf's Li-ion 18650 battery achieves a new energy-density milestone (electrek.co)

 

 

[alcatraz]

I'm seeing chinese made and original Tesla made 4680 cells being sold in China now. Few of them are original, most are chinese versions and they're close to 300Wh/kg density. Impressive. 

Here are pics of original cells being sold in China now. Maybe they're even being manufactured there now. I remember production of Tesla's 4680 wasn't originally in China. Importing stuff into China is expensive so I'm surprised to see them on the market.

[alcatraz]

Here are pics of the chinese ones. Some are claimed to be BYD (chinese motor vehicle company) and some have other battery manufacturers' names.

These aren't the highest density, possibly Lifepo4. There are high density cells at near 300Wh/kg too.

These pictured ones are offered as 4680 15Ah for 49cny and 46120 25Ah for 68cny. 

[alcatraz]

These are branded 亿纬 Yiwei and are 90/95/110mm 28/30/38Ah. They're 10C for a short time and that's 280-380A amp draw depending on each cell. 5c continuous. Impedance is almost 1ohm. They're 250-300Wh/kg density. They cost 80-110 cny per cell. No weight specced. Another product looking similar had a weight specced at 385gr for 38Ah. I'm not sure if these are too.

Edited October 4, 2023 by alcatraz

[alcatraz]

Another product for 82cny

亿纬46950三元圆柱电芯 Yiwei Lipo
3.7v  标称30ah  实测32ah branded 30Ah, measured 32.
尺寸：46mm*95mm dimensions
重量：416g weight
内阻：1.1mΩ左右 impedance
模组（拆机）都有 
高倍率支持15C放电 15C discharge
三个12v即可启动汽车打火 3 of these can start a combustion engine

32Ah and 416gr make 285Wh/kg.

Edited October 4, 2023 by alcatraz

[skunkmonkey]

On 9/6/2023 at 12:51 PM, mhpr262 said:

I wonder when the first wheels featuring the 50S will turn up

I saw on Wheel Good Time today that e-wheels is going to release the V14 with 50S battery packs. I’m not sure if all vendors are, or if that’s specifically just e-wheels, but either way it’s good news for the trail riders.

[MetricUSA]

And where exactly are you going to put those monster batteries on an euc??? We desperately need solid state batteries for travel and safer wheels... 

[alcatraz]

Just saying that these are actually available and they're not 5 times the price. The wheel manufacturers are nearby this market.

You don't need the same amount of cells. You can build packs with one of these per cell "group". Physically they're not much larger than four 21700 cells (4P) which we see on most eucs. 24S4P, 20S4P, 32S4P.

A pack using these is also more likely to be repairable. You don't need a thousand spot welds, or perhaps any welds.

I'm not pushing for it. I'm just interested in what's available at a reasonable price and that has leading energy density. More range for less weight.

Neither a new big brand cell or these chinese cells can be guaranteed to not burst in flames after 1/2/3/4/5 years. They need to be used with good bmss and then we'll find out. For now they're in regular cars I think.

Edited October 4, 2023 by alcatraz

[mhpr262]

Making a replacement pack for my V10F out of those chunky boys in a 20s1p configuration would be WAYYY easier than making a 20s4p pack from the original cells. Provided they fit of course. I guess one would have to make a "dummy pack" from 3D printed cells to test it beforehand.