Quick-Swap Battery Modules

[teddillard]

I've been working on a quick-swap battery module idea, actually, obsessed would be a better word. It makes perfect sense to me - most e-bikes run a pack that you can swap out easily, every power tool manufacturer has a standard battery that fits a range of their products. I have a motorcycle, a dirt bike, a scooter and a lawn tractor that could all use the packs... and after eleventy-million versions, this is my latest:

[youtube]TVAt4BwnJ4s[/youtube]

This morning I made a few changes, including mounting the receiver higher to eliminate the hanging connector, making the mount more compact. Here are some photos:

More here: http://evmc2.wordpress.com/2013/03/10/battery-module-detail-shots/

It's set up to be a 40ah 14.8V module using Turnigy hardcase (RC lipo) packs. Two of them would give me the ~36V for the scooter and the tractor. 3 or 4 of them would give me all I need for the dirt bike, and 5 of them would kick the motorcycle to 74V.

Thoughts? Suggestions?

 

[jonescg]

I like the concept, but the trouble is, the power is better when the battery is bigger. C-rate is always a function of capacity.

Modular batteries up to 48 V each for things like the lawn mower, the e-bike, the chainsaw and the brushcutter is a great idea. I'm shocked more hardware makers aren't doing it actually. The power demands of a motorcycle are such that you'd never want to run anything than full capacity.

Nice modules though. I like the fixed Anderson!

 

[teddillard]

So, bear with me here... Let's say you want to double the capacity. You simply wire the receiving harness to parallel two modules, then series the pairs, right? Then you have 80ah @ 74V, for this particular pack.

...or, you just build them bigger. This module would weigh about 10lbs with the cells installed. A 20lb module isn't horribly heavy.

 

[scoot]

Well I really like the "proof of concept" model you're working on... very clever and functional IMO. Should be very stable and protective, as well as convenient.

I imagine you'll be modifying the screw attachment system for the Andersons so there will be no soft pack puncturing possibilities. In the end I guess it is mostly about obtaining the ideal box dimensions for any given application. The coolest aspect from my point of view is how you can remove/install the packs so quickly... with all of the obvious advantages and possibilities that capability can afford. 8)

 

[teddillard]

Thanks! Yes, the brackets for the mount are going to be tigged, and the bolts for the Andersons will be flat head and covered. At the very minimum I'm going to have some sort of rubberized layer inside for insulation, and have looked into a fireproof pouch for the RC lipo.