Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Busbar for 150a continuous 300a peak
#1
Hi All, 

Busbar sizing 5x 6mm2 twisted 

Going by googling different specs I think this should handle 150a continuous with spikes of 300a

Anyone else with any tips for high currents?

Andrew
Reply
#2
We cant tell because we dont know what size it is. 20cells with 300a is huuuge.. thats 15a per cell. Beware that higher current just slightest resistance in the busbar Will cause the cells closest to the connection to have higher load. Up to 30a Id wrongly done.


What is the size of that bar? Do you going to run The oposite om the other Side? And what Wire do you Connect the cells with? (You cannot have cell level fuses on that high current. It wont work)
The Ultimate DIY Solar and build place
YouTube / Forum system setup / My webpage  Diy Tech & Repairs

Current: 10kW Mpp Hybrid | 4kW PIP4048 | 2x PCM60x | 100kWh LiFePo4 | 20kWh 14s 18650 |  66*260W Poly | ABB S3 and S5 Trip breakers
Upcoming: 14S 18650~30kWh
Reply
#3
Cells are 12.5ah 1c continuous 3c peak LiFePo4 new cells.

Bar is 5 strands of 6mm2 building wire twisted together about 34cm long. Can just squeeze it into 35mm2 lug

Was going to run cell level fuses but was afraid of resistance overall.

Opposite +ve and -ve to get was even as possible draw on pack
Reply
#4
Should be fine then. But you are in the top end of current on the cells.
The Ultimate DIY Solar and build place
YouTube / Forum system setup / My webpage  Diy Tech & Repairs

Current: 10kW Mpp Hybrid | 4kW PIP4048 | 2x PCM60x | 100kWh LiFePo4 | 20kWh 14s 18650 |  66*260W Poly | ABB S3 and S5 Trip breakers
Upcoming: 14S 18650~30kWh
Reply
#5
Should I just run thicker copper strands instead of fuses?
Reply
#6
As daromer pointed out above, due to bar resistance, you should have the lugs at opposite ends of the pack to get more even resistance & cell load distribution.
Take it this is for a short term use, eg < 1 hour run time & shorter cell life is accepted?
Also, the cells are likely to get warm (at least) when loaded hard like this.
Running off solar, DIY & electronics fan :-)
Reply
#7
Yes you need thick wire between busbar and the cells. I wouldnt consider them fuses since those will be so thick that that are way above what the cell can handle for it to be a proper fuse.

Just make sure you have decent pack-fuse instead.
The Ultimate DIY Solar and build place
YouTube / Forum system setup / My webpage  Diy Tech & Repairs

Current: 10kW Mpp Hybrid | 4kW PIP4048 | 2x PCM60x | 100kWh LiFePo4 | 20kWh 14s 18650 |  66*260W Poly | ABB S3 and S5 Trip breakers
Upcoming: 14S 18650~30kWh
Reply
#8
Thanks daromer and redpacket.

Will let you know how it goes!
Reply
#9
How do you intend to attached the connection to the cells? I would not solder for a high drain application like this.

Would it be possible to consider spot welding 0.2mm or 0.3mm nickel strip to the cell and soldering to the buss bar?
Reply
#10
Spot welding if for sure possible but i would say soldering should be ok. It is in the high end current for sure and spot welded nickel strip doing 30A is alot Big Grin
The Ultimate DIY Solar and build place
YouTube / Forum system setup / My webpage  Diy Tech & Repairs

Current: 10kW Mpp Hybrid | 4kW PIP4048 | 2x PCM60x | 100kWh LiFePo4 | 20kWh 14s 18650 |  66*260W Poly | ABB S3 and S5 Trip breakers
Upcoming: 14S 18650~30kWh
Reply


Forum Jump:


Users browsing this thread: 1 Guest(s)