The Hundred Dollar Ebike Battery

[antboy]

Mine is a 20MM can I believe. It's quite large and can hold 2ea 20Ah triangle packs.

Thanks! "20MM" was the secret search term I needed to find ones that could fit Silverfish style batteries.

I MIGHT still go with the tool box, but let's face it, ammo cans are cooler.

 

[tomjasz]

MIGHT still go with the tool box, but let's face it, ammo cans are cooler.

The ammo can lid can be very securely latched and still allow venting with the lid gasket removed. I drilled 2" ports and bought rubber grommets from Amazon.

 

[harryS]

GerogeS posted about those surplus hoverboard packs in 2017. I was skeptical, but after reading some good test results, I bought a few and configured two 60 dollar 36V8AH batteries that I still use in 2020. There were some safety concerns. because they set up the charger connection wrong, but it wasn't hard to fix that. I store them in ammo cans or in cinderblocks.

Last year I bought some surplus segway/ninebot scooter batteries from the same seller in the first post. These were very well made. Machine welded batteries with sturdy battery forms. Dual temp sensors. The BMS only worked with ninebot chargers, so I replaced that. Made two 75 dollar softsided 36V10AH packs that I considered very safe. but they still get stored in a fire resistant area like the above packs.

 

[tomjasz]

There were some safety concerns. because they set up the charger connection wrong,

What did you do to change the connections?
Thanks!

 

[harryS]

What did you do to change the connections?
Thanks!

The hoverboards charged the packs thru the output connector, bypassing the overvoltage protection. If/when your charger failed, and went above 42V, you had the overcharged hoverboard fire.

I attached 5.5mm round connectors to the unused charger inputs. My original move was to replace the BMS, but after doing one, I realized I only had to add the connector,