Anything better than 18650-25R?

Important parts emphasized.

OK I took a break after not having a bike but I got a decent full susp bike to convert and am thinking about batteries. Right now I have a 19s5p 18650-25r (~800Wh, nominally 100A continuous) pack that's working well but it's soldered and I am concerned about longevity since I regularly treat my bike very rough. I chose the 25R because of its balance between cost, high current delivery, good capacity with moderate drain, and extremely resilient chemistry (for a battery with this kind of performance). So I'm going to make a more reliable pack that also addresses the shortcoming of my current pack which are lack of good engineering / construction and meager 800Wh energy capacity.

ANYWAY, the priorities for this next pack, which I intend to make 20s, are...

--high energy to mass ratio
--high capacity of battery overall >1Kw certainly
--high current draw without stressing battery (we'll say 50 amps)
--good marginal effect of my dollar (no need for stuff with BETTER performance I won't use)


For this next pack I plan to spot weld if I use cells.

So, which batteries should I be looking at for this next pack? I want as much capacity as I can get while spending under, say, $800.

You might want to take a look at this thread in the sales forum:
Tesla Model S 18650 cells! Welded Packs! Panasonic; NCA
https://endless-sphere.com/forums/viewtopic.php?f=9&t=67661

Interesting, I will keep that in mind but now I'm leaning toward the Samsung 18650-30Q in a 7P 20S configuration. Can I do better???

The LG 18650 HG2 has same capacity and I think higher continuous current. It's what I'm considering for a small powerful pack.

Hobbyking graphene?

Gregory said:

The LG 18650 HG2 has same capacity and I think higher continuous current. It's what I'm considering for a small powerful pack.

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Now that's a good suggestion! Do you know of a good source here in the USA? I can get the 30Q for $4.36 apiece shipped from USA which is not much more than HG2 from China and I am not super eager at the possibility of getting a counterfeit battery off Alibaba which if I even manage to catch early on will be infeasible to send back for refund...

cwah said:

Hobbyking graphene?

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I heard about these on the RC helicopter forum since I picked up that hobby while not riding my e-bike, and while the batteries are supposed to be really durable I think they're more expensive and heavier for a given capacity. I am still really interested but I don't think very many people have used them yet and I'm not sure where I'd buy for a competitive price for >1KW of capacity.

I plumped for the 30Q over the 25R - the performance is basically the same but you get an extra 500mAh.

The HG2 are also supposed to be good, but the price premium over the 30Q was too much for me for the slightly better (from memory) performance.

I think you might like the Panasonic/Sanyo NCR18650GA. https://batterybro.com/products/panasonic-sanyo-ga-ncr18650ga-3450mah-10a

Comparing GA vs 30Q for a 5A discharge with 3V cutoff:
GA => 3Ah
30Q => 2.6Ah

That Panasonic has a really impressive energy density. The 30Q still has the best price / performance and good discharge capacity. Right now I'm thinking about a 20s7p pack of 18650-30q for 1.5kwh and strong discharge performance. I'll need to do more research tho because I want this next pack to support 50+mph with a hub motor.

I heard about these on the RC helicopter forum since I picked up that hobby while not riding my e-bike, and while the batteries are supposed to be really durable I think they're more expensive and heavier for a given capacity. I am still really interested but I don't think very many people have used them yet and I'm not sure where I'd buy for a competitive price for >1KW of capacity.

Click to expand...

I have 4 2s2p 50.2 v 32 amp yes they are heavier (11 kilos with padding cables and straps) and bugger me expensive.. they are strong though, my old pack (multistars) would sag down to 44.2 volts and get very warm at 12s 50 amp these sag to 47.6 and stay cool at 12s 60 amp