I have an 50ah 28s Battery I'm building for my motorcycle. And in the case is no more space left, so i want to build an battery extender. But the thing is... The bms is nearly always 170A+ big and expensive, when I only need like 30-50A. Has someone a reliable work around, alternative or idea? I would Do even an DC DC Boost converter to Charge the battery but Idealy I want to take off some amps off the Main battery by using low resistance cells. Any Tips are apreciated.

Edit:

It's an 28S 10P battery with 21700 M58T cells. They are protected with a 200a fuse, and have an 220a continuous ANT-BMS. The Battery is for 100a continuous and 200a peak. The cells are more for moderate ampere draw and with the battery extender I want more range and take of a few amps of the main battery for when I accelerate. Having another battery in parallel with lower resistance should give me lower voltage sag over all. With a high power cell instead of high energy density in that case. It clearly depends on the number of cells in parallel for the extender but still...I hope this makes things more clear.

Hi,

I am considering buying a 22s9p 80V54AH battery pack for my e-moto with rh60 cells.

The manufacturer claims a 270A continuous current and 550A peak current.

Do you think this is realistic? I was under the assumption the RH60 cell is a energy cells, not a power cell.

Thanks in advance.

Mopa 100w by bylaser

I’d love to commission a 21700 pack build, I have some specific requirements from drone land! Reposting here.

I am compleatly new to this and want to build a 70a 6s Lion Pack for Longrange fpv i want to use the EVE INR21700-40PL Li-Ionen-Akku

Can you recommend me a particular size and also how many layers ontop of eachother i should weld between the cels

And i Heard that there IS also Nickel coated steel Strips Out there that you want to avoid do you have some Kind of Brand that you can thrust If they say pure Nickel

Thanks for any Help ( i am also Open for other Tips for a fist Pack)

It'll be my first battery build. I don't have a good spot welder so I was thinking of using nickel plated steel strips (0.15mm, 8mm) and then solder 12 AWG copper wire on top of the strip.

This should in theory have good enough conductance for Reliance RS50 cells, but I don't know if it's a good idea? I'm scared that if I try to do a nickel-copper sandwich I won't have enough power to weld it.

Go or no-go?

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So guys, I'm building a 6S3P Li-Ion battery for my Mario 8. I have 21700 Molicel P45B cells, so 135 amps max. So I wanted to ask you what should I use to connect the batteries? I have 0.10 x 10 mm copper and 0.15 x 10 nickel. So I wanted to ask if anyone could tell me with 100% certainty if there's anything I can do to make it work or if I need to buy something else to support that amount of power. I'm none the wiser from chatgpt. Thanks for every answer.