Wednesday, November 12, 2008

Battery Hoax

Lead is poisonous. It causes damage to the brain and nerves, and to other vital organs as well. Even in low doses it can accumulate in the body over weeks and months and cause terrible, permanent damage, even death.

Lead can be absorbed into the body from contaminated air or water or food, even from soil and house dust.

Lead used to be used in a lot of things--in gasoline, paints, plumbing pipes, ceramics, toys. It can be a very useful chemical. But because it persists in the environment and is so toxic, it has been legally banned from most of those uses.

Except batteries. Lead batteries pack so much electricity per dollar that they have been difficult to replace--especially car batteries. About 3/4 of world lead production goes into car batteries--over 5 million tons a year.

It should be reassuring to hear that car batteries are efficiently recycled; it is legally required, in fact, the recycling cost is built into the purchase price. Supposedly over 95% of car batteries are recycled, so their lead does not go into land fills or toxic waste dumps to pollute and poison the environment, it goes back into more batteries.

Or does it?

Car batteries can be made with a lead-antimony alloy (which CANNOT be recycled cost-effectively into batteries) or a lead-tin alloy (which CAN be recycled into batteries--which, by the way, last five times longer than lead-antimony batteries).

So far so good: all we have to do is make new batteries out of lead-tin and be reconciled to junking the old lead-antimony batteries until, in a few years, the supply dies out. But the trouble--one part of the trouble anyway--is that it is hard to tell the difference between the two kinds of batteries when they come for recycling: batteries are not marked "lead-antimony" or "lead-tin." So most lead-tin batteries are thrown in with the lead-antimony ones, "recycled" into junk, and shipped overseas (because of U.S. laws) for discard.

Moreover, lead-antimony batteries keep being made. Why? Lead mines want to keep mining lead. That's how they make money. They would rather not have the lead from car batteries recycled. And car-battery manufacturers want to make batteries that must be replaced every couple of years--replacement is how they make most of their money.

So year after year most car batteries are still made with lead-antimony instead of lead-tin, and are "recycled" after a couple of years into junk lead (shipped overseas) while new lead is mined to make new batteries. And even the lead-tin batteries that are made, when they finally wear out, get junked with the lead-antimony ones.

That's the "battery hoax."

What needs to be done? Lead-tin batteries need to be clearly labeled (despite industry pressure). In fact, lead-antimony should go the way of tetra-ethyl lead in gasoline and lead in house paints, plumbing, toys, and ceramic glazes--it should be illegal to manufacture lead-antimony batteries.


Addendum--non-lead batteries

[Quoted from The Free Encyclopedia on the Web]

The nickel-iron battery is a storage battery having a Nickel(III) oxide-hydroxide cathode and an iron anode, with an electrolyte of potassium hydroxide. The nominal cell voltage is 1.2V. It is a very robust battery which is tolerant of abuse, (overcharge, overdischarge, short-circuiting, and thermal shock) and can have very long life even if so treated. It is often used in backup situations where it can be continuously charged and can last for 20 years. Its limitations, namely, low specific energy, poor charge retention, and poor low-temperature performance, and its high cost of manufacture compared with the lead-acid battery along with its having a lower energy-to-weight ratio led to a decline in usage.

[Also from The Free Encyclopedia]

A nickel metal hydride battery, abbreviated NiMH, is a type of rechargeable battery similar to a nickel-cadmium (NiCd) battery but has a hydrogen absorbing alloy for the anode instead of cadmium. As in NiCd batteries, nickel is the cathode. A NiMH battery can have two to three times the capacity of an equivalent size NiCd and the memory effect is not as significant. However, compared to the lithium ion chemistry, the volumetric energy density is lower and self-discharge is higher.

Applications of NiMH-type batteries include hybrid vehicles such as the Toyota Prius and consumer electronics. The NiMH technology will also be used on the Alstom Citadis low-floor tram ordered for Nice, France; as well as the humanoid prototype robot ASIMO designed by Honda. Standard NiMH batteries perform better with moderate drain devices such as digital cameras, flashlights, and other consumer electronics, but, because NiCd batteries have lower internal resistance, they still have the edge in very high current drain applications such as cordless power tools and RC cars.