Which inverter to get

[TheChamp]

The problem, hope it's the only one

 

[TheChamp]

So i assume the jump starts failed

Yea new bms and then the cells are still usable again

Yes, it wakes up okay, charges for a few seconds then shows full voltage and the charger switches off.

 

[leon.davibe]

Found on powerforum

 

[TheChamp]

Good news is that the battery looks okay.

 

[leon.davibe]

The problem, hope it's the only one

View attachment 1527173

Too thin metal strip for the rating probably

 

[leon.davibe]

Yes, it wakes up okay, charges for a few seconds then shows full voltage and the charger switches off.

Yea the voktage is probably only on bms and without a connection to cells the voltage rises up quick and says full

 

[TheChamp]

Too thin metal strip for the rating probably

You are 100%, the cables are fine, the metal strip is just too dodgy.

 

[wingnut771]

Too thin metal strip for the rating probably

even for the half a second when the fridge spikes?

 

[wingnut771]

You are 100%, the cables are fine, the meta strip is just too dodgy.

How did you fix it?

 

[leon.davibe]

even for the half a second when the fridge spikes?

Maybe they bent that strip one too many times during manufacture

 

[wingnut771]

Maybe they bent that strip one too many times during manufacture

maybe

 

[TheChamp]

How did you fix it?

It's still not fixed, the strip burnt clean of just where the positive of the battery starts, so the cable was able to handle the current, things fell apart where it had to transfer to the strips.

I am going to try find a clean spot to solder the cable.

 

[TheChamp]

Maybe they bent that strip one too many times during manufacture

maybe

The strip is just not good enough, but there was indeed a bend where they rolled it onto the cable before soldering. It shouldn't have been a problem though.

 

[leon.davibe]

What ah rating is the battery

It's still not fixed, the strip burnt clean of just where the positive of the battery starts, so the cable was able to handle the current, things fell apart where it had to transfer to the strips.

I am going to try find a clean spot to solder the cable.

Yea and then only parralel the battery so it doesn't have to carry all the load as the strip is clearly undersized for amps

How many cells in total

 

[TheChamp]

What ah rating is the battery

Yea and then only parralel the battery so it doesn't have to carry all the load as the strip is clearly undersized for amps

How many cells in total

50Ah, there were two in parallel. Both dead.

40 cells in total, 3.2V, 6Ah each.

 

[leon.davibe]

It is a spot welded strip hey?
If it was the threaded one you could add a busbar like tjis and put a lug on wire

 

[TheChamp]

It is a spot welded strip hey?
If it was the threaded one you could add a busbar like tjis and put a lug on wire

Yes, spot weld.

 

[wingnut771]

50Ah, there were two on parallel. Both dead.

40 cells in total, 3.2V, 6Ah each.

Both burnt in the same spot? Using a busbar to parallel?

 

[TheChamp]

Both burnt in the same spot? Using a busbar to parallel?

Yet to open the other one, I am just suspecting it will be the same.

I was using cables to parallel.

 

[leon.davibe]

Yea i would extend the wire and solder it the full length of the last row of cells so that the full load does not go over a single strip
Instead of just on the edge

Adding i diagram in case i am expressing kak

And then on the parralel wire have two stripped that long and soldered on both packs like that

Or since it is 2 rows you could split the wire and solder on both lines of cells