batteries
| Parts infobox | |
|---|---|
| Image |  |
| designers | Timothy Schmidt |
| date | 2018 |
| vitamins | |
| materials | |
| transformations | |
| lifecycles | |
| parts | Frames, Nuts, Bolts, End caps, Controllers, Wires, Ferrules, Electrical connectors |
| techniques | |
| tools | Wrenches, Soldering irons, Crimpers |
| files | |
| git | |
| suppliers | |
Introduction
Challenges
Solar PV panels are inexpensive and durable. As are the power conditioning electronics. Batteries, however, are expensive, prone to failure, and often discarded as trash. Can we reduce trash output while solving our expensive battery problem?
Chemistries:
- Lead acid
- Lifepo4
Approaches
Recycle batteries from the trash stream to build new, high capacity, long lasting battery packs.
Battery (Recycled 18650 lipo cells)
Rationale:
Single battery system from tools → teslas. I'll be bringing these tools in with me, to work with:
And here's what I've purchased to build my battery - note they're all available with prime shipping, except for the BMS, which probably won't arrive in time for the first build day. The battery I'm building is 48v, or 13S (13 cells in Series). For other voltages, you might find a BMS available with faster shipping.
Tools
Parts
Development targets
Battery charging for the universal controller
Brass / Steel Battery - http://pubs.acs.org/doi/ipdf/10.1021/acsenergylett.6b00295
- Coroplast box cell container
- Frame / caster racking system
- Charge controller?
Printed 18650 battery container block - spring-loaded (printed springs?) contacts +
locking door. Serviceable fuses and diodes
Development History
v0
v1
Soldered 18650s, 7s20p configuration w/ 20A BMS.
v2
Based on 18650 NESE Modules. 7s7p configuration w/ 20A BMS x2, MPPT-7201A solar charge controller and DC-DC buck-boost converter, 500W motor controller, modular frame + quick disconnect pins.
v3
Purpose modeled replimat printed part w/ printed springs, zinc plated steel 5×1 plates as electrodes, lock-nutted electrode studs, USB power, 20p5s.
Off the shelf
Cell testing
- Attiny84 has 8x 10bit ADC, 640, 1280, 2560 have 16x 10bit ADC