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The brouhaha in the mainstream media about exploding batteries in cellphones and notebook PCs is real. Consumers are worried. Check out the recent Good Morning America show.

Pundits also point to large lithium-ion batteries in electric and hybrid vehicles. What would happen if one of these batteries short-circuited, got punctured, or caught fire in a collision?

According to Toyota’s Prius Emergency Response Guidebook 154, the cells in a Prius contain potassium hydroxide that can react with zinc, aluminum, tin, and organic compounds, releasing potentially explosive hydrogen gas. Potassium hydroxide is also a hazardous material. In fact, Toyota technicians are required to wear alkali-resistant safety goggles, face masks, rubber gloves, boots, and aprons when handling vehicular battery packs. Toyota and Honda also recommend that crash rescuers use the same equipment while working on wrecked vehicles.

Reliable And Safe

Accidents aside, it's probably next to impossible for a nomadic device's battery to explode. If you electrically mistreat a battery, that’s a different story. I once hastily overcharged a small nickel-cadmium (Ni-Cd) battery used for a radio-controlled model airplane. The pack overheated and started smoking uncontrollably. In a bit of a panic, I stopped the exothermic reaction by dumping the whole affair in cold water. Thankfully, the pack submerged completely in the men's room commode!

Are there dangers with today's batteries as used in cellphones and PCs? Certainly. Can exothermic reactions occur in normal use? Not likely. You have to grossly mistreat a battery to cause it to burst into flames or explode. It’s a matter of proper handling.

Proper handling includes how a battery is disposed of. Getting rid of your old rechargeable battery is easy. The Rechargeable Battery Recycling Corporation will help you do it correctly. RBRC is a non-profit organization that reclaims metal from old rechargeable batteries (RBRC also collects used analog and digital cellular telephones, but that's another story). RBRC collects Ni-Cd, nickel-metal hydride (Ni-MH), lithium-ion (Li-ion), and small sealed lead-acid batteries. The RBRC Call2Recycle program recycles these used batteries in an environmentally friendly way.

If you view the RBRC safety video, you'll discover there are Federal laws about how to send your spent batteries through the mail. The tutorial warns recyclers to never place more than one battery in a plastic recycling bag, in order to avoid possible shorts. However, in RBRC’s video, the narrator explains that the batteries “may get hot." Reading between the lines, it's clear RBRC avoids the E word (explosion) in its call for proper handling. Hhhmm.

Extreme Experiments

If you want to go ahead and drive a ten-penny nail into a fully charged Li-ion battery to see what might happen, be my guest. If you want to sidestep that extreme hands-on experiment, check out this on-line presentation.
 
Regardless of hype, and staged explosions in controlled laboratory environments, there have been battery recalls. Lots of them. The US Consumer Protection Commission has issued no fewer than 1.6 million Li-ion battery recalls since the year 2000 (ask Dell about that). Check it out here. 

Pirate and aftermarket Ni-MH batteries are also flooding the market. Just do a Web search for your laptop’s replacement battery and you’ll see what I mean. Batteries for sale from Web retailers may or may not contain proper internal charging circuits or thermistor temperature monitoring. Even if they are built with well-designed protective circuits, battery maker Valence Technology contends that thermal runaway can still occur. Valence's safety video vividly depicts what happens when oxygen-fed thermal runaway occurs in a standard Li-ion battery pack.

Valence says its batteries are much different. They’re constructed with a patented phosphate-based Li-ion chemistry that contains no metal oxides, and there’s no heavy metal to recycle. Valence claims its fail-safe chemistry also conveys extended cycle life. Its batteries are also lighter and smaller than competing battery technologies.

They key to these claims rests in the fact that Valence's stacked polymers are based on electrolytes that plasticize the polymers, eliminating free liquids in cells. Unlike competing Li-ion batteries that require heavy metal casings to retain liquid electrolytes, Valence's polymer batteries are packaged in lightweight foil.

Along with what it says is superior energy retention, Valence's phosphate-based Li-ion batteries are also compatible with lead-acid charging systems. In fact, the company makes batteries that are available in popular lead-acid sizes. Most are World Trade Organization-compliant, too.

Valence’s claims notwithstanding, I don’t worry too much about brand-name original equipment Li-ion or Ni-MH batteries in my portable products. I don’t intend to crush my battery packs in a vise, puncture them with bullets or nails, or toss them into my barbecue. I trust the folks at my town’s recycling station know how to handle them, too. Nonetheless, I must admit today’s battery powered portable designs can pose potential problems for unwary end users and folks who come in contact with them.

What’s your experience with batteries and battery chemistries? Write me at amm at en-genius dot net, or post your comments below on our blog.