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[Supervstech]

No, I am sure they still can be used, they need to be compressed though.

 

[Supervstech]

What is your plan to connect to the lugs on the ends?

 

[danphillips]

I'm pondering several options:
-low temperature solder - In my application I dont think the cells will get too how
- Spot weld
- drill a hole on the post and tap it - I have already drilled about the distance the post sticks out of the battery, when I get the nerve I'll try to go deeper. The post is a solid metal with copper on the inside. (I have spare battery to experiment on)

 

[Supervstech]

I'm pondering several options:
-low temperature solder - In my application I dont think the cells will get too how
- Spot weld
- drill a hole on the post and tap it - I have already drilled about the distance the post sticks out of the battery, when I get the nerve I'll try to go deeper. The post is a solid metal with copper on the inside. (I have spare battery to experiment on)

I do hope you are videoing the procedure!

aluminum post with copper inside?

 

[emdrei]

Dan,

Like you, I am working with limited space on a boat. What are the dimensions of the individual cells?

 

[danphillips]

the outer post I believe is not aluminum, or is a hard aluminum alloy - see attached

 

[danphillips]

battery size is 16 1/2 (with posts) x 6 x 2

 

[nicpaige]

I am fabricating some main post clamps for these batteries out of solid copper bar. I will post pics if it is a success.

 

[maxx123]

I would solder a copper round stock heat the bar up first, add flux add solder nice and hot put in a little flux in its hole heat it quicky and install,

was thinking one could thread it, metal too soft, you should have left the bars on, I was surprised you took them off. leaves very little room to play with,, Great video

 

[maxx123]

I am fabricating some main post clamps for these batteries out of solid copper bar. I will post pics if it is a success.

like this? used the copper that came with the battery

 

[danphillips]

Maxx123, That loos great

 

[Maast]

I just finished up a quick break down of the BYD 24v battery from https://www.batteryclearinghouse.com/. These batteries are stout, well designed and HEAVY !
The batteries have 2 posts for positive and 2 posts for negative. The bridge between posts are not a solid bar, they are made up of about 100 layers of a thin metal, I presume to allow for expansion and contraction.

Hey Dan, did/could you measure continuity between the two battery posts on one end of the battery cell?

I'm wondering if its one cell with two posts per polarity (which seems a little odd) or actually two cells in the square cell pack and each 24v module is actually 16 cells. With the way the BMS circuit traces are only attached to one side it suggests its just one cell in there but it's worth finding out.

Because if it is - hooking up BMS leads to the bussbars would require one lead per bussbar or some sort of bridge between the two with a BMS lead attached to the bridge.

Thanks!

 

[maxx123]

Maxx123, That loos great

Thank you,I am impressed by how all the snap-on covers interchange

 

[maxx123]

Hey Dan, did/could you measure continuity between the two battery posts on one end of the battery cell?

I'm wondering if its one cell with two posts per polarity (which seems a little odd) or actually two cells in the square cell pack and each 24v module is actually 16 cells. With the way the BMS circuit traces are only attached to one side it suggests its just one cell in there but it's worth finding out.

Because if it is - hooking up BMS leads to the bussbars would require one lead per bussbar or some sort of bridge between the two with a BMS lead attached to the bridge.

Thanks!

16 cells in 8 batteries, odd to me, it is not a bms it more a monitoring system by byd, if you notice it hooked up to + ------- bms is - ++++++

 

[nicpaige]

like this? used the copper that came with the battery

This first iteration fits on the posts on the front of the case, yours looks like a good solution.

 

[maxx123]

I did not like it at all, my situation the battery will be on top of each other, easier access on the side. for the limited space, bolting casters to the bottom to the heat shield, save on my back in case i need to move them.

 

[batteryclearinghouse]

We have the 8 individual BYD batteries from the Dan's destruction video... we can send those out to some folks to experiment with various post/bus bar modifications.

They appear to very similar to the other BYD battery cells I have seen so it would be great to figure out the best/workable solutions.

 

[Maast]

16 cells in 8 batteries, odd to me, it is not a bms it more a monitoring system by byd, if you notice it hooked up to + ------- bms is - ++++++

Not odd at all, very similar to the way the nissan leaf cells are arranged: 1 "cell" is actually a 2p2s assembly. If the BYDs are 2 cells per block that would make them originally 110AH cells, which could make sense as the relatively economical and light 200+AH cells are very recent - these were constructed 2014ish and their weight corresponds to the earlier LFP formulation.

 

[Maast]

We have the 8 individual BYD batteries from the Dan's destruction video... we can send those out to some folks to experiment with various post/bus bar modifications.

Please! I'll even pay for it. If you send one my way, I've got a 20A-300A individual 3.2V cell capacity and lifecycle tester I just built to evaluate the big blue 280AH cells from alibaba. I was in the process of evaluating several cell models from various chinese vendors prior to buying a bunch of them then I saw yours.

I'd LOVE to have a individual cell to test the snot out of.

 

[maxx123]

We have the 8 individual BYD batteries from the Dan's destruction video... we can send those out to some folks to experiment with various post/bus bar modifications.

They appear to very similar to the other BYD battery cells I have seen so it would be great to figure out the best/workable solutions.

glad i asked you when you first took them apart, Was trying to help your buddy figure out how to re mount the connections, in a way he should have left the busbars on.. then again go wild, think clamps and strapping is needed to suck in that bulge,