Thundersky battery issue

[micart671]

Hello,

I'd like to start a debate regarding the Thundersky (Winston) battery cells.

I have recently been told that these cells will not function correctly when laying on their flat side as the electrolyte eventually settles and exposes the upper plates, reducing capacity. The retailers (Australian) of this product say it's not an issue.

A friend used them in his EV and apparently just the ones laying flat failed and now they are upright, no problem (after being resurrected)

Any help will be greatly appreciated,

Cheers,
Mic

 

[jonescg]

Hey Mic,

A moderator might prefer to move this to the batteries forum, but in any case yes I have seen Thundersky cells fail lying on their sides. Perhaps laying a cell on it's side exposes the top 2% of the cell's layers to complete electrolyte drying, while laying it on edge would expose less than a few percent of all plates to the same problem. I think the early incarnations of large format cells were more prone to this, but later versions have moved towards multiple pouches per block, kind of like the 16 'watertight' compartments of the Titanic, but in reverse

Chris Swain's electric suzuki suffered a similar fate; his flat laying cells were the first to show reduced capacity. I do know that the most preferred orientation of all lithium sandwich cells is upright, but that's fairly useless on a motorcycle.

Chris

 

[heathyoung]

There has been anecdotal evidence of this, the majority suggest that the cells can be laid flat on their short side (not long) due to the wicking effect of the layers.

If they are placed on the long side, then the top layers dry out. Thundersky I think said this at some stage.

 

[micart671]

It's funny... ever since i heard of this issue, i have been laying the Postie bike on it's side (when not in use of course )

 

[SniperGaulois]

How many cycles did you get with these, what chemistry are they, thundersky used to do Cr batteries and now it's LiFePo? what capacity are you getting since then?

 

[dumbass]

I have been using the same ThunderSky packs for about 5 years now. They are the old yellow 20ah lifepo4 cells. Their built into multiple 24v packs. The individual cells are stacked on their side within the packs. After 5 years of they are still delivering a min. of 14ah. There is 1 cell in each pack that drops it's voltage below my alarm's set point of 2.80v. So I don't think I could blame the side stacking as the problem or just poorly balanced cells. While in winter storage they are also in the same side position.

Bob