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Old 04-07-2016, 04:45 AM
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Quote:
Originally Posted by mulligan View Post
Aren't those the ones that explode ??
Before I start into some facts, I find this question somewhat funny coming from people who have been sitting on top of tank of liquid gasoline as they travel down the road. It is highly flammable and can explode if the conditions are right.

What if a gas golf cart was hit by car?


If your gas tank is punctured it is sure to spill all over the ground and create an even bigger hazard. In a report from 2005 over 266,000 gasoline related car fires killed over 566 people. So with that said, I will begin to approach the subject of the dangers of lithium ion fires.

The metal lithium is highly flammable and burns very hot.
But lithium ion cells like those use in most electric cars these days do not actually contain metallic lithium.

So not the same issue with these batteries.

Rechargeable, lithium ion cells utilize lithium ions that are intercalated into graphite, lithium metal oxides and/or lithium salts.

There is no metallic lithium in a lithium ion battery.

This means that they are much more stable than many of the earlier non-rechargeable lithium batteries which did contain metallic lithium.

One big safety factor in this is that you can use standard ABC fire extinguishers or water to put out a lithium ion battery fire.

It is in the charging process that they may be vulnerable.
If you over charge a lithium ion cell the cells will expand and become very hot.
If over charged to much, this heat will build up and cause the cell to ignite.
During the normal charging process the cells should not become hot.

This is why it is very important to have some kind of monitoring system hooked up to the cells while they are being charged to make sure that the charger shuts off automatically when they reach a fully charged state or if the cells become hot.

All of our systems have a State of the Art Battery Management system.


last point we are not using 4 large 12 volt battery packs to make 48 volts

We use 15 3.2volt batteries to get 48 volts,

so if there was a problem the battery mass is significantly smaller to cause damage.

A gas can in your garage offers a greater risk perhaps.


The way the battery charger works when plugged into you homes power automatically disconnects from the battery pack when full charge is reached.

they can't overcharge.


.