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View Full Version : A little A & S from a "cager"




recumelectric
07-01-08, 03:40 AM
This actually falls more in the category of safety, so I won't be posting about ice picks, guns, and anti-aircraft guns. :D

I've been dealing with an auto mechanic for about a month now (long story), so we've actually started discussing some off-topic stuff. I brought up the issue with me trying to select a safe, efficient, and lightweight battery for an electric motor for my bike.

His advice to me was, regardless of which battery you choose, always use goggles and rubber gloves when dealing with the battery. He told me a pretty intense story about one of his mechanics who had a lead-acid battery blow up on his face and hands. The car was turned off, and all he did was touch it with a wire (kind of like the wires we like for re-charging). Fortunately, the mechanic was wearing goggles, which had been dissolved by the acid by the time they returned form the ER. Skin damage was minor, as he flushed everything off right away. The people in the ER said that the goggles had literally saved his vision.

...And it was a 12 Volt battery! I think the ones being sold with most kits and electric bikes are 12, 24 or 36 Volt.

I realize that I may have an elevated sense of risk with these, but it is because I have been doing a lot of research. I'm concerned that a lot of folks out there may be hastily purchasing things in the midst of the "gas crunch," and may not know how to properly handle things. I just want everyone to be careful with the batteries. Safe is better than sorry.

WJChris
07-01-08, 08:36 AM
I can imagine there were stories like this all over the place when Gasoline was introduced as a motor vehicle fuel.

Whenever modifying or working with any battery, I agree on personal protection. Better safe than sorry.

maddyfish
07-01-08, 09:06 AM
I have seen automotive batteries blow up and spew acid. It doesn't seem unreasonable to take precautions.

evblazer
07-01-08, 11:41 AM
I used to work on 120 - 258 volt Pba (lead acid) packs. I always wore a face shield, long sleaves, long pants and gloves and had plenty of baking soda around (usually just wore a mechanics jumpsuit). Electrically insulate your tools which means if you use a wrench electrical tape the rest of it so you don't short out two terminals.

One of my friends and I also had a NICAD battery explode during charging that was exciting. IIRC vinegar was used to nuetralize the KOH in Nicads as opposed to the Baking Soda for the acid in Lead Acid batteries.

Both of those cases were with flooded batteries. I have seem the absorved glass mat batteries pop a top off and they don't get everything all mess but it is still worth taking care.

As far as gasoline you could spill it all over your hand along with motor oil and diesel and no it isn't good for you but it won't burn/melt skin. Just do some research on how to clean up after the battery you use. Water might not be the best thing. It may even make the situation worse.

recumelectric
07-01-08, 10:06 PM
I can imagine there were stories like this all over the place when Gasoline was introduced as a motor vehicle fuel.



I'm sure there were, until people began to understand safety precautions and the technology was improved. ...And everyone here is quite familiar with the risks still associated with gasoline powered vehicles.

So, the risks will probably never be entirely elimated. I guess we'll have to learn to manage the risk instead.

...And those are some pretty scary stories that I read from the rest of you guys. Any advice on how to extinguish a fire with a NiMH? I already know that water is definitely not the way, since it can cause a build up of hydrogen gas, leading to explosion.

evblazer
07-02-08, 08:28 AM
...And those are some pretty scary stories that I read from the rest of you guys. Any advice on how to extinguish a fire with a NiMH? I already know that water is definitely not the way, since it can cause a build up of hydrogen gas, leading to explosion.

A quick search shows
http://www.evworld.com/news.cfm?newsid=18262
"Sand will immediately put out flames on lithium, a highly flammable material, Clow said."

GP Batteries MSDS for all NIMH cells
"Extinguishing Media: Carbon Dioxide, Dry Chemical or Foam extinguishers"

cerewa
07-06-08, 12:32 AM
Pretty much every type of battery is capable of burning itself up in a couple seconds or exploding. As mentioned earlier, batteries are as dangerous as gasoline. Don't allow accidental short-circuits to happen at any voltage - the results of a short circuit won't be too different whether the voltage is 12 or 100.