Sanyo 20700a vs 20700b.. questions

I was looking at these cells, and it looks like they now have an even better looking ‘C’ option. 3500mAh, 30A, 12.6Wh.

https://voltaplex.com/panasonic-c-20700-battery-ncr20700c

One thing I consider for using these more expensive cells, regardless of the extra cost of needing a BMS, charger, cables, etc… is that if you were to buy a battery pack from nearly every builder, that the total cost of the pack makes the average cost of a cell usually around $10/cell. Obviously there are cheaper/pricier exceptions, but it seems like they’re usual that expensive. So the way I justify paying that much for a larger pack is I could either pay ~ $600 for a battery pack from a pro builder for a 12s5p with 30Q’s, or I could pay the same amount, build it myself, and use these new high capacity cells. Of course I could just use 30Q’s to make the cost like half or so, but I am not overly concerned with the cost for such an important part of the project.

I will start build threat soon, thanx

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It’s my own design 3d printed,

removing torsional flex, waterproof, stress relief on the batteries, cell level fusing, isolated routing for balance wires.

But still working on finishing the build.

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How does Panasonic’s reputation hold up to Sanyo in regards to the 20700s?

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Well I’m not 100% sure of this but I think Panasonic and Sanyo are essentially the same thing regarding the manufacturing of those cells. Like they partnered up, say like Toyota and Scion for ex. If you Google Sanyo NCR20700A/B/C, it’ll show those cells with the Panasonic name.

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I think you’re right. Welp time to start looking at places to buy those C’s at.

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The 20700a’s with twice the amp rating should reduce voltage sag substantially over the 20700b’s Range is increased when voltage sag is reduced. I don’t know if it would be enough to make up the difference in capacity but as for myself, I would go with the 30a rated cell.

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So would I. If I wanted the extra range, I’d go with 30Qs instead.

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Have you checked the xyxlea for those cells? I’m just curious.

Maybe i’m missing something but even the 20700B will outperform most 18650 batteries.

With the bench testing of “mooch”, 30Q/ HG2/ 20700B are all rated for 20a continous (30Q on it’s limits)

The 20700B will have the same voltage sag as most 18650 batteries. Of course 20700A will be even better but looking at voltage sag in our application, the 20700B will definitely have the best of both worlds, increased capacity in limited space.

30Q

20700B

HG2

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Not true, just because the battery is limited to 30A doesn’t mean that the motors will be, at anything less than 100% duty cycle the motor current can be higher than the battery. Max motor current = battery current / dutycycle So at lower speeds you can easily feed huge current to the motors with a low battery current

@Pedrodemio Let me revise my statement: You’d be able to feed each motor controller 30 amps.

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I think it’s a common misconception that 30Q have better discharge rate than 20700b. The benchmarks that I saw also show 20700b being superior in discharge, voltage sag and capacity departments.

I guess since you saw it it must be true.

samsung 30q vs sanyo 20700b discharge results

image%20(1)image

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Did you realize you just copied the same charts from a few posts above, which was the message I was replying to in agreement?

I did not copy those. I went to mooch’s page.

Not my point though.

Might be easier to see when everything is plotted on the same chart:

image

What am I missing here? Why isn’t 20700B better?

Samsung 30q’s are great for 20a, nit 15. Regardless of what Samsung says. It’s been proven here a 100 times.

Hey man you look like a real pro on this , i am building 12s5p pack , for raptor hub motor , i am better with samsung or sanyo ?i want crazy power and range ! Probably already respond to this but i don’t understand sh*t on those graphic … Thanks man

I would go with 30Q’s, they are proven robust and perfect for the application.

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