LiPo battery replacement for lead-acid + relocation

buzzvert · Post by **buzzvert** » Sat Aug 24, 2019 2:25 am

In my bin of "things I should install on something" resides a wonderful dual Nautilus horn. It's a big mother, and I could get creative and mount it behind the front windshield (as PGO calls it, the front plastic) but am toying with a new idea-

The existing battery box beneath the mat is pretty big and exposed to road hazards, which sort of worries me. I'm sure it's fine and nobody ever has had it whacked by a curb etc. but with the loads of unused space in the front of the bike, it would be a logical place to put a different form factor and much lighter LiPo equivalent to the lead/acid stock form factor. I could then plop a big-ass horn into the battery area and have it blow itself silly from the underbike.

Has anyone else thought this through?

babblefish · Post by **babblefish** » Sat Aug 24, 2019 2:38 am

I did that with my Blur, am working on a LiIon (18650 cells) replacement for the Buddy but it will be in the stock location. One thing to keep in mind if you're making your own battery pack is to make sure you use a BMS (Battery Management System) so that your lithium battery has a long and healthy life and doesn't burn your scooter to the ground. With the Lithium battery the Blur starts really fast plus the battery weighs about a third what the stock battery weighs, is half the size, and is 10 Ah.

buzzvert · Post by **buzzvert** » Sat Aug 24, 2019 2:44 am

babblefish wrote:I did that with my Blur, am working on a LiIon (18650 cells) replacement for the Buddy but it will be in the stock location. One thing to keep in mind if you're making your own battery pack is to make sure you use a BMS (Battery Management System) so that your lithium battery has a long and healthy life and doesn't burn your scooter to the ground. With the Lithium battery the Blur starts really fast plus the battery weighs about a third what the stock battery weighs, is half the size, and is 10 Ah.

Thank you- exactly what I needed. I'm going to keep it where I can switch it back to stock if necessary and run heavy gauge from the floorboard to the front cluster area- and choose a battery form factor that will best fit where the stock horn area is- likely wide and flatter. The BMS is something I had not thought of and I'll work to integrate that into the design. I'll keep a set of jumpstart leads under the floorboard so I don't have to pull plastic if things are drained as well.

babblefish · Post by **babblefish** » Sat Aug 24, 2019 3:31 am

When shopping for a BMS, make sure you get one rated for at least 50A because the Chinese manufacturers can be very optimistic with their specs.
I run a 3S (three cells in series) pack in the Blur.

iwannascoot · Post by **iwannascoot** » Sat Aug 24, 2019 11:34 am

babblefish wrote:When shopping for a BMS, make sure you get one rated for at least 50A because the Chinese manufacturers can be very optimistic with their specs.
I run a 3S (three cells in series) pack in the Blur.

Could you post a link to a BMS so I know what to look for, please.