That’s a great question! The first line of defense is always prevention (isolating live battery terminals, properly stacking/packing/storing batteries so they cant touch in ways we dont want, etc.) but we also have fire alarms, yes.
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Sorry, I’m not one of the 2 mentioned mods but i thought I’ll help out.
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I couldnt remember if you had the power to move posts, I didnt mean to leave you out Marcel 
Many thanks for your assistance!
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Ok, I’m clocking off for the night (my shift was supposed to end hours ago 
). I’ll talk to y’all more on Monday (though I’m sure that damn duck will be around to answer some questions in an entirely unofficial capacity 
).
Happy Thanksgiving to you all!
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Just so everyone is aware Benji was my first and most favored concubine, so I’ll be taking first dibs on all the good loot. Sorry, not sorry, etc.
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Unfortunately it has the same implications for customs
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New phone. Who dis?
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@Flasher is correct, international is international as far as customs is concerned. It might be possible in the future, but for the time being we are focusing on the contiguous United States.
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I feel like a real professional 
This is a battery module from a Honda Fit EV, which is made by Toshiba with their 20Ah SCiB cells. They are LTO chemistry, so 2.7V fully charged, but they are a seriously impressive cell. I’m excited to get these listed.
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LTO are so dope! You can run that cell all the way down to 0v and charge it back up!!! Not sure exactly how much energy ithas at super low voltage levels, but its a super cool chemistry for sure
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The $$ for just the voltage isolation in that board is higher than entire esk8 BMS’ parts costs.
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Toshiba states a 1.5V end-of-discharge for these cells. I have no idea how well they would handle recovering from 0V, but it would certainly be interesting to see!
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Could you explain more about this?
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They will absolutely be damaged but, like any li-ion chemistry, the voltage level and the time spent at under its rating determines the degree of damage. It’s cumulative so if it just happens once then there might be no noticeable effect. But if it keeps happening, or undervoltage for a long time, then the damage can get a lot worse.
Some chemistries can be less susceptible to this but I don’t know much about which are worse or better. If a cell has a low voltage cutoff rating though then going below it is not good for the cell.
If any cell could be brought to zero volts without damage then the manufacturer would make that a huge part of their marketing and it would be in the datasheet. It would make long term cell storage and shipping much easier and safer.
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I think that all the components I’ve circled are dedicated to getting power and/or data across a voltage isolation gap, including that custom transformer ($$$).
Each module would need power and isolated data lines in order to talk to the “brain” for the BMS. Since each module is probably at a different voltage, in series, they would blow up the master controller (“brain”) if connected directly.
The Texas Instruments web site has good info on EV BMS systems as they have some very capable automotive BMS controller chips. You can go down a verrry deep rabbit hole with stuff like passing ISO26262 testing, being ASIL compliant, and other safety-related automotive stuff that these BMS’s need to handle.
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Are there any numbers on these two big chips?
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Yes, I’ll get you those numbers when I’m back into work on Monday. Thanks for all the info John! As always, your insights are invaluable 
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I’ll expect a dozen on my porch by Monday morning.
Don’t forget my cashew milk decaf Americano this time Benji or I’ll be leaving a rather scathing Yelp review.
(Seriously, what’s the ballpark on these? And since when did you become the village drug dealer?)
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Do you ship to Iceland ?
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If you plan to buy an EV battery, then no.
no idea about small stuff tho
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