LI-po battery safety

[r4e]

How much heat is generated by the battery during the NORMAL charging process?

Do you need to consider ventilation / heat dissipation during charging. Sealing a battery up
in an insulated, airtight container sounds like it "might" present a problem.

The LipoPacks would have the same problem, if there is any problem concerning conduction of any normal heat generated during charging. However they are not airtight - the idea is only to delay the exit of gases and allow them to react with air in a partially enclosed space.

I am guessing that any insulation might possibly speed up a thermal runaway situation. The delrin case of the battery pack is insulation as well. However, if the original problem is a cell chemistry failure or an internal short circuit in a cell and this causing heat, this affects the LiPo chemistry and additionally might cause insulation failures in neighboring cells --> locally fast cascading events and thus probably not affected by external insulation.

A different question is the charger, because this definitely will generate heat due to internal losses. Unless the space is large and/or ventilated, I would not place the charger in the same box.

Monitoring the internal temperature of the box should be easy. Just place a meat thermometer through the box lid. 30 degrees centrigrade is already an elevated temperature, LiPo batteries should not be charged at temperatures over 45 degrees centrigrade, and, internal breakdown of the LiPo battery might commence as low as 70 degrees centrigrade. The temperature zone between these would be heat stress. Perhaps one could build a thermally controlled shutdown for the mains supply to the charger?

If building the box from plywood, I would consider having a loose internal lid in order to make the exit path of gases a bit longer.

[MichaelAngelo]

The one I built has a shelf on draw slides so it pulls forward and the scooter on bottom is open air. Think of it in terms of a blast shield instead of Box. Plenty of ventilation but if you had an issue it deverted away for the house.

[belgian]

my 2 cents to keep my house from burning...
I use a big metal pot that slips over the battery , a cheap plug in timer that cuts of the power after a set time (i give it 1 hour more that full charge), and a thermostat that cuts the power when it feels any heat.

[ARY]

Thick sock of natural leather is good enough to contain 4-5Ah LiIon fire, just leave gas products relief channel. Pack each individually.

[Jax]

I learned a lot from here.

When I charge my batteries, I make sure I sleep with appropriate clothing.

[FW]

I learned a lot from here.

When I charge my batteries, I make sure I sleep with appropriate clothing.

You mean like Andrew?

On a more serious note, you can buy charging bags for smaller LiPo batteries, like in a dive light. They just don't make one for scooters, yet.

[RebreatherPro.com]

Heres the blast box I built at H2O. Bottom is cement blocks while the top is a HUFFY Steel tool box. Scooters fit in the bottom, cannister light up top. I also wired the power to a 6 hour timer, (similar to the timers for bathroom heat lamps) Now just gotta built the child seats to make your joke be completely true.

We had a fire in our blast box just about 7 weeks ago. The box contained the fire, and we put it out with extinguishers. Kinda scary. Now, we built a freestanding metal shed on a sand pile about 100 feet from the house, and put two ventilated metal cabinets inside. And extinguishers nearby. Pics to come.

[FW]

We had a fire in our blast box just about 7 weeks ago. The box contained the fire, and we put it out with extinguishers. Kinda scary. Now, we built a freestanding metal shed on a sand pile about 100 feet from the house, and put two ventilated metal cabinets inside. And extinguishers nearby. Pics to come.

Light, or scooter batteries?