LiPo Rules

[SamM]

I think it may be a good idea to have a discussion and then add somewhere(not sure where) an extensible section about LiPo batteries and rule considerations for them. I feel there is a lot of variation in how different events treat them: no rules, charging rules(lipo sacks,etc.), restrictions on certain weight classes(Franklin Inst), match rules(Forfeit if battery comes out, even if still working/connected. Forfeit or restart? if fire is put out and robot still works, etc.)

I feel there should also be a best practices section somewhere for LiPo considerations for EOs: fire extinguisher class, sand bucket use, safe firefighting plans (inside arena, or in safe, pre-planned location outside[fire cart plan/path needed]), arena ventilation, etc.

[FingerTech]

Code: [Select]

SPARC_Match_Rules_v1.0.pdf
(Option) Should the battery of a robot become exposed the match will be halted and the robot with the exposed battery will lose by TKO.So that one is up to the event.  It either goes on, or it's an immediate loss.

Lipos are always allowed unless the venue says no.  That's not something that needs to be written in the documents.

The Tournament Procedures might be the best place for a What-To-Do guide for lipos. 

From the big events I've been to: The fire is extinguished then the bot is carted outside in case it flares up again.  Someone stands by with the extinguisher ready while the builder removes the lipo to be put into a bucket and covered with sand.
For small events, the only difference I imagine would be that a "cart" is impractical.  What's the best way to carry a bot outside that isn't bare hands?  Maybe a cart IS the way to go.  How about a fire blanket overtop too (for big- and small-bot events)?

What kind of extinguishers work?  Or DON'T work?  That would be useful to note in the docs.

Does arena ventilation need to be addressed?  What would you suggest for it?

[MikeNCR]

For smaller events, toss it into a big metal bucket is a common approach. Perhaps a supplimental document "Lipo Best/Suggested Practices" or similar with info on what types of extinguishers work, where to get them, suggested protocols, etc... would be handy.

[zacodonnell]

While we're on the topic, what kinds of extinguishers are you guys using for lipos? I think I saw Ed use a CO2 extinguisher to knock down the HyperActive fire last year but I'm not sure that's what it was.  What kind of damage to the bot do the various types of extinguishers do?  Obviously knocking the fire down is vital or the bot is a total loss anyway, but are there compounds that can stop the fire without gumming up / shorting out the rest of the bot?

-Zac

[irobotchuck]

At my events I keep a CO2 extinguisher on hand.  They are the best I know of to "knock down" a Lipo fire.  I also keep a metal bucket with a lid 1/2 full of sand and another bucket with sand to cover the lipo.  I also have a pair of fire gloves on hand for handling bots or Lipos that could explode.
These are the suggestions I have gotten, but I would also like to know if I am doing what I need to and if there is more I could do to make the event as safe as possible.

Chuck

[zacodonnell]

The process you describe matches the couple of events where I've participated in putting out lipo fires.  One extra thing to add is a clear path between where you put the burning robot in the trash can at the arena and a door that leads outside so you don't have the fume and smoke problems inside any longer than necessary.

-Zac

[Koolaid64]

for small bots a shovel is sometimes the best way to remove them from the arena. keeps the danger past arms length.

[ACME]

What kind of extinguishers work?  Or DON'T work?  That would be useful to note in the docs.

From my research, D type extinguishers (for metal fires) are the only ones that can actually extinguish a lipo fire. However, D type extinguishers cost more than some robots. For small bots, using an ABC fire extinguisher to keep everything else from catching on fire and smothering the battery with sand seems to be an effective way to deal with lipo fires.

[Lucas Grell]

As far as ventilation, the area around the arena should be fairly large, and not closed in, but that's really up to the venue. I don't think any kind of active ventilation is necessary.

I'd also imagine that making sure there's an easy route from the door of the arena to wherever the battery needs to go would be a good plan. Maybe carrying it with welding gloves or similar would be smart, and definitely at least glasses, if not a mask in case it flares up.

Would it be feasible to mandate relatively quick removal of the battery pack? The quicker it gets in the sand, the better.

[FingerTech]

A story I heard last week about the D class extinguishers.

A friend of mine works for a company that builds electric vehicles and they make a battery pack that has over a hundred cells in series/parallel.  Someone accidentally installed one cell backwards and upon testing the cell quickly began to vent.  They thought it would be a good time to try out the D class extinguisher and so wheeled the trolley outside and sprayed the cell - but surprise!  The foam in those is conductive!  So now instead of one venting cell, the entire pack was shorted out.  This led to a much bigger fire that the extinguisher could not cope with.  The fire department didn't even know what to do with it.  They just watched it until it was spent.

So I'm happy with our CO2 extinguishers and sand buckets.

[TeamAstroBot]

A story I heard last week about the D class extinguishers.

A friend of mine works for a company that builds electric vehicles and they make a battery pack that has over a hundred cells in series/parallel.  Someone accidentally installed one cell backwards and upon testing the cell quickly began to vent.  They thought it would be a good time to try out the D class extinguisher and so wheeled the trolley outside and sprayed the cell - but surprise!  The foam in those is conductive!  So now instead of one venting cell, the entire pack was shorted out.  This led to a much bigger fire that the extinguisher could not cope with.  The fire department didn't even know what to do with it.  They just watched it until it was spent.

So I'm happy with our CO2 extinguishers and sand buckets.

surely someone has video of that spectacle!?