3KWh DIY Lifepo with 2,5KW Inverter in a nice Case (IMO 😅)

legacyturbo

Solar Enthusiast
Here is my little Solar powered Island.
- 8x 120AH Lifepo4 Cells from Alibaba
- Chargery BMS
- Victron Battery Protect
- Victron BMV 700
- Inverter ECTIVE TSI 25
- PowMr MPPT SCC

I use the electricity for some circuits in my house, for example a fridge, coffee machine, TV and lighting. The inverter switches to the grid when the battery charge is low. It is controlled by the bmv.

The chargery is only a part of safety, it switches two tiny relays (each 0.2w) The two relays switch the Battery Protect. when the Chargery is triggered, the Battery protect switches off all consumers and the inverter switches to grid. The system can then only be restarted manually using a button. 😅
 

Attachments

  • IMG_20200708_190610.jpg
    IMG_20200708_190610.jpg
    49 KB · Views: 55
  • IMG_20200708_190518.jpg
    IMG_20200708_190518.jpg
    90.3 KB · Views: 58
  • IMG_20200708_190204.jpg
    IMG_20200708_190204.jpg
    56.7 KB · Views: 60
  • IMG_20200708_185952.jpg
    IMG_20200708_185952.jpg
    55.6 KB · Views: 63
  • IMG_20200708_144955.jpg
    IMG_20200708_144955.jpg
    49 KB · Views: 63

sremick

Mostly competent. Knows enough to be dangerous
No, i dont know why i should do something like this.
Prismatic LiFePO4 cells like to expand and contract a little even with normal use, and a lot if something goes wrong. Even that little bit can put strain on hard bus bars like you're using, which can damage the terminals and/or the inside of the cells. And if one cell catastrophically fails, you can damage adjacent cells as a result.

By using compression, you keep the batteries' desire to expand in check and the innards from moving around. In fact, many manufacturers require compression in their datasheets (you may see it referred to as "fixture").
 
Top