Boeing announced late Friday that it will delay delivery of its new 787 Dreamliner due to problems with its large battery.
American aviation authoritiesS.
After two aircraft operated by Japan Airlines had a battery failure, new jets were also grounded abroad, including a battery burned when the plane landed. These lithium-
Ion batteries are new for jets.
They are powerful and lightweight, and unfortunately they are also fragile.
\"Everyone has lithium with them.
\"The ion battery is in your pocket today,\" said Vince Bataglia, a chemical engineer at Lawrence Berkeley Lab in California.
Mobile phones, laptops, cameras
Small appliances thrive on them.
\"There is no big problem with them rising in flames from time to time \". Lithium-
The voltage generated by the ion battery is twice that of the traditional battery.
When they go bad, energy becomes heat.
Battaglia says it\'s not a big deal because the battery is usually smaller than a small finger.
\"The energy is small.
It\'s easy to remove heat from a small battery. A small battery will soon lose heat.
But if you enlarge the battery, such as the size of the big suitcase, it\'s hard to get rid of the heat.
\"When you go to these larger cells, you already get all the heat in one cell,\" Battaglia said . \".
\"You have to get it out.
\"You can do this by using a fan or circulating coolant around the battery.
This works fine as long as the battery is intact.
But chemical engineers know lithium.
The ion battery has a fatal weakness for two reasons.
One is the fluid inside the battery, called the electrolyte.
The Yin and Yang ions flow back and forth through the electrolyte, thus generating electricity.
Electrolyte is an acid water in a normal battery. In lithium-
It is a flammable organic compound.
Donald Sadoway, an engineer at MIT, pointed out, \"If you really get to the temperature, you have fuel. It\'ll burn.
\"You can get the heat because of the second weakness.
It is a film inside the battery that regulates the flow of ions in the electrolyte fluid.
If the membrane breaks, the flow of ions gets out of control and the fluid heats up.
Sadoway said: \"You broke this membrane and now you have two compounds that want to react violently to each other and there is nothing to stop them from doing so.
\"If the weather is hot enough, the electrolyte liquid will evaporate and escape.
Think about the brandy you pour into the hot frying pan and light a little flame.
Laptop Batteries sometimes burn like this.
This is the case with a Chevrolet Volt electric car.
After a controlled collision test, the electrolyte of the battery became loose and the car was burned clean.
Battaglia, Berkeley, says the batteries are delicate.
He said he would drive with lithium.
Ion battery, but he is worried about what happens when the inner membrane is damaged.
\"If I had an accident, I wouldn\'t have taken it into my garage and plugged it in,\" he said . \".
But Sadoway at MIT says the batteries are certainly safe to use.
\"We know what possible failure patterns are and they can be defended,\" he said . \".
You can take these lithium.
The ion battery is definitely bulletproof, safe, and there are other ones, but the question is, what is your price?
\"Who is willing to pay for it compared to other batteries?
The price may be too high for the automotive industry.
John Hansen, Toyota\'s environmental and safety manager, said the company had
Electric cars.
The company trusts them.
But Toyota is looking for alternatives.
\"The only thing we are against lithium is that in order to develop the cars that the mass market will buy in the next step,\" he said, \"they have to be cheaper and they have to provide more scope, we can\'t get these from lithium.
\"However, their future on the plane may depend on what engineers have learned from two incidents on Dreamliner.