Arrma 4600mah NiMh battery Question

[ajdragon]

Hi

By any chance does anyone know what the C ratings would be for the Arrma 4600mah NiMh battery back? I put mine into my Pro MT 4x4 with a WP-SC8 ESC, and 2100kv motor, and the battery got really hot after one short run, and I figure the C rating may have been way to low for the WP-SC8.

 

[olds97_lss]

Guessing NiMH is just way too low for any 1/8th scale system. Fine for nitro with servos and smaller/lighter 1/10 vehicles that are to be run on 2S, not great, but ok. My 90C 2S packs in my outcast come out of the truck pretty warm, 115F on most days, 120F when it's 80+ outside. Pretty sure I'd melt the solder right off the cells of a sub-c pack. lol!

These 4500's are 30A max:
https://www.batteryspace.com/nimhrechargeablecellscsize12v4500mahflattop-30arated1pc.aspx

I know my MMX data log in my savage flux shows 120A spikes with a 40-80A+ draw on most pulls. That's twice what those NiMH cells can supply.

Wish I had spread that log out a bit wider, but I was trying to see all that was logged.

 

[ajdragon]

Hi

The info is very helpful, I think I'll just us this pack in my Raider XL from now on.

 

[Jerry-rigged]

Hi

By any chance does anyone know what the C ratings would be for the Arrma 4600mah NiMh battery back? I put mine into my Pro MT 4x4 with a WP-SC8 ESC, and 2100kv motor, and the battery got really hot after one short run, and I figure the C rating may have been way to low for the WP-SC8.

I've read most nimh packs are in the 10c-15c range.

 

[ajdragon]

Hi

I came a cross this video last night, and from what they are saying running below minimum C rated packs on modern BL ESC's can damage the capacitors over time and shoten the life of the ESC. This makes me wonder if using a NiMh battery "with a much low C rating" in my Raider XL with the 80 amp ESC might be doing damage to it.

 

[Jerry-rigged]

The more important question is - what is the amp draw of your motor? If you have one of the common 3300kv motors, pushing a lightweight 2wd car, with moderate gearing, you don't have a huge load on the batteries, and a decent Nimh can do OK. If you have a high power system, then you will be overloading the batteries, and can damage them.

I just don't see ruining an ESC (due to nimh) outside of doing something like speed run pulls.

 

[ajdragon]

Hi

The Raider is run a 80 amp ESC and 3600kV motor.

 

[Jerry-rigged]

Yeah, that seems like it is getting big for nimh. Might be time to start thinking about lipo.