In case of fire...

Hi guys
I had a question about the danger of lithium packs. For example say if i had a few 4s lipo packs all wired in series but are separated physically from each other and by chance one of the packs got punctured and started smoking like crazy etc.
To limit the damage id have to quickly disconnect that pack from the others IF POSSIBLE DURING PANIC MODE, and discard it. However would the undamaged packs be at risk also of catching electronically when the 1st pack started to smoulder/ignite? Once i cut the series wiring then would the only problem by that 1st pack?
Nothing like this has happened..knock on wood. Just wanna be mentally prepared if anything does.
Thanks!!

Step zero

never have them anywhere unsafe to just let them burn out

Can you explain a bit more about the packs....and their intended use?!

Why would they be exposed to the risk of puncture for instance. The first thing i'd look at is how to better protect them.

Having said that, do each pack have their own bms, or is it shared/satellite? As long as each has over current protection and you have it wired with fuses on the series then one shouldn't affect the other. It's difficult without better understanding your situation I think.

john61ct said:

Step zero

never have them anywhere unsafe to just let them burn out

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The are mounted on the bike..not in storage or anything.

SanchoSanchez said:

Can you explain a bit more about the packs....and their intended use?!

Why would they be exposed to the risk of puncture for instance. The first thing i'd look at is how to better protect them.

Having said that, do each pack have their own bms, or is it shared/satellite? As long as each has over current protection and you have it wired with fuses on the series then one shouldn't affect the other. It's difficult without better understanding your situation I think.

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Yes im doing my best to orotect them..They are in use on the bike itself. Im just thinking if i had an accident ot something and 1 pack got damaged..would it be a domino effect or just the single pack would be at risk? No bms at the moment

Can you give some more detail on the packs? Ideally the battery type and chemistry. Is applicable number of series and parallel cells in each pack, whether there is anything between the packs to provide protection (even if it was just a fuse)

I may be able to help a little more with a greater level of detail. I know this sounds totally obvious and is probably not what you need, but if you are worried about it then it probably means they are too exposed or may not have the circuit protection needed. Trust your gut.

SanchoSanchez said:

Can you give some more detail on the packs? Ideally the battery type and chemistry. Is applicable number of series and parallel cells in each pack, whether there is anything between the packs to provide protection (even if it was just a fuse)

I may be able to help a little more with a greater level of detail. I know this sounds totally obvious and is probably not what you need, but if you are worried about it then it probably means they are too exposed or may not have the circuit protection needed. Trust your gut.

Click to expand...

They are just hobby king 4s packs but 5 of them in series with no bms. Im just wondering if ever 1 gets punctured for whatever reason, would the other undamaged packs start to catch fire as well since they are wired into the damaged pack? Or would i only need to worry about removing the single damaged pack? Thx

ebike11 said:

They are just hobby king 4s packs but 5 of them in series with no bms. Im just wondering if ever 1 gets punctured for whatever reason, would the other undamaged packs start to catch fire as well since they are wired into the damaged pack? Or would i only need to worry about removing the single damaged pack? Thx

Click to expand...

They'll be fine. As long as the burning pack is physically isolated, the electrical connection won't hurt the others.

Agreed with Sam on this. The only thing to add in my view is a fuse on each series connection. Just to be safe against any overcurrent due to malfunction in each pack. Fuse it to the level of the highest C value of each pack, or 10-20% higher than the max current required.