Arim, you sound like just the guy to address some of the safety issues with safe chemistry batts and Li-ion batts. We've all seen the results of flame and pressure discharge in pictures here and on other sites. I wonder what percentage of batteries experience this and how widespread it actually is. The laptop battery fire scared a lot of people, but the government reports don't support the hype that appears from actual cases. The laptop fire cases were extremely small compared to the number of laptops in use during the period and the problem existed temporarily due to a faulty production run of batteries that were later recalled.
Is there anything you can point to in addressing the hype or supporting it?
I have been testing high performance batteries for the better part of 15 years. Way before there was any commercially available PV's. I can tell you, without a doubt, that the hype is well deserved. I have seen some catastrophic failures of poorly designed batteries....and it ain't pretty. I have watched thousands of dollars of electronics go up in flames. Thankfully I have never seen anyone get hurt....as we all knew what was going to happen when we were doing these tests, and when we weren't sure...we stayed FAR away from the test area.
ANY...I repeat ANY battery can become dangerous. If a cell is handled poorly, designed poorly, or it's protection fails...it basically becomes a bomb. At the very least you get off-gassing, and let me tell you breathing in fumes from a battery venting is not at all pleasant.
So here comes the part that is relevant. If you abuse a battery (some people are just asking for trouble) it will fail. The level of severity of that failure runs the gamut....from a battery that ceases to function...to quick limb removal. Again it all depends on the power of the cell, and how much stored energy needs to be released when the cell goes into thermal runaway.
On that note, I do have to say that the "battery industry", as a whole, has done a remarkable job in designing proper protection for cells. Am I saying that it's impossible to get hurt? NO!!! However one could argue that an idiot with a butter knife can be dangerous. It's like anything else. Treat the battery with some common logic...do your homework...and don't stab 4kw lithium cell array with a fork (just to see what will happen).
ANY battery can be dangerous, and well designed, well protected batteries can be very safe. To answer bluntly...there is NO "safe-chemistry" battery. Some chemical make-ups are just "safer" than others.
It's so difficult to make blanket statements or generalizations with batteries/electronics. It's all so specific. I can assure you though, that the laws of physics remain constant on Earth (at least for now). If you try to defy those basic laws, you will get hurt...or at the very least learn an expensive lesson.
I for one don't worry about the safety of the batteries I use in my PV's...as I have done my homework and have raw experience and data to predict what should and should not happen. I do have great concerns over others safety though...especially people who are sold "fake" xyz cells. It is utterly shameful for someone to go out and sell unprotected Lithium-Ion (and let's not even get started in Li-Poly) batteries as "protected". That is a REAL danger and it's very hard for the general public to know what is and what is not safe.
Man talk about me being on a soapbox. Sheesh. I am really glad you brought up the issue of battery safety though. It's very important (in my opinion) and I am more than happy to lend any information I may have about the subject. I hope I don't come off as a know it all in the process...because I am still learning about these things everyday. I am always open to ANY legitimate data that shows a conclusive result. Science begins with an open mind....
P.S. I am doing an AW LiFePO vs. Tenergy LiFePO shootout over the next few days. If anyone is interested in the outcome feel free to PM me.
