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Pics/Info: Inside the battery pack

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Hi, I am new to this forum. I teresting original post and comments from the community. I have a question regarding BMS board. I am hoping you'll be able to answer. I bought 4 Type S Tesla batteries to use as 48V storage battery bank in a Solar Electricity production off-grid project. So the radiator fluid was drained out already. If I leave the BMS board on the module and charge the battery bank with solar panels, will it do any harm to the battery? In other words, will the software on BMS malfunction as it can't control the temperature by pumping coolant? Or will it still balance cells?
BTW I am planning on using MPP hybrid 6048 splitphase inverter (Taiwan company), these can be connected in parallel to get 3-phase electricity.
Appreciate your effort and time in sharing your findings with the world.
The boards on each module are a small subset of the BMS. I've looked at them in detail years ago and as I recall they're basically a TI BQ76PL536 cell monitor, microcontroller, and a communication isolator. They can report cell voltage & temperature, but can't control it directly. They can only barely balance the cells (although the necessity of that is way overstated given the large number of cells in parallel). The only way the larger BMS can control the temperature is by controlling the coolant pumps, valves, radiators, heaters, AC unit, etc to get to the desired temperature. That said, as long as you keep the cells in the appropriate range (which should be 20-30C or so) you should be in good shape. Remember that the car packs routinely deliver 1000A or more, I suspect your load will be much lower which should make it a lot easier to maintain their temperature. If they're in a conditioned interior space you probably don't need to do anything special to heat/cool them.
 
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The boards on each module are a small subset of the BMS. I've looked at them in detail years ago and as I recall they're basically a TI BQ76PL536 cell monitor, microcontroller, and a communication isolator. They can report cell voltage & temperature, but can't control it directly. They can only barely balance the cells (although the necessity of that is way overstated given the large number of cells in parallel). The only way the larger BMS can control the temperature is by controlling the coolant pumps, valves, radiators, heaters, AC unit, etc to get to the desired temperature. That said, as long as you keep the cells in the appropriate range (which should be 20-30C or so) you should be in good shape. Remember that the car packs routinely deliver 1000A or more, I suspect your load will be much lower which should make it a lot easier to maintain their temperature. If they're in a conditioned interior space you probably don't need to do anything special to heat/cool them.
Wow, thanks for quick response. This gives me adequate peace of mind to go ahead with my project. I understand there is no harm done in leaving the the PCB BMS board in tact for my application. Yes, my inverter is only 6000W 120/240 a/c, so nowhere near 1000A.
 
Dear All,

Does anyone here have some information of the valves in the bottom of the battery casing?

There are 6 of them shown on wk057' picture 2014-09-09 2021.21.31.jpg. wk057 call them "some kind of safety relief vales".

I believe they are meand to drain the battery casing from condensate, and at the same time to block any inflow of water from the inside, fx if the car is parked in 6-7 inches of water, after heavy rain. A one-way-valve in other words.

I need similar valves for a project, and I have searched everywhere I can imagin, but without luck.

I also asked wk057 if he had some of them in excess, but unfortunately he throw them out as they was not useful for his project. :-/

Any information, such as a brand, vendor, data, more pictures, or a link to an alternative valve with similar funktion would be helpful ... and ofcourse; if anyone has one or more samples, I would be very interested to buy.

Thanks 😄
i know this is old but in case someone else needs it.
1677778352845.png

not sure if this is same/newer/older design...
 
does anyone know what this other small orange cover is for on newer packs? ( i know left one is the pyro fuse)
looking at some battery teardown videos on youtube, there doesn't seem to be anything going there on inside of pack...
maybe a valve?
i'll open it up later but wanted to ask first.

1677778493160.png
 
does anyone know what this other small orange cover is for on newer packs? ( i know left one is the pyro fuse)
looking at some battery teardown videos on youtube, there doesn't seem to be anything going there on inside of pack...
maybe a valve?
i'll open it up later but wanted to ask first.

View attachment 913009
To answer my own question, 3 of the same valves that are along the battery and a breather.
1678838617807.png