moncler it The Electric Cooling Battery Test_10958

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Liquid cooling systems can carry heat away from battery cells more quickly than ventilation cooling. Additionally, "liquid cooling is many more contract," says Bill Wallace,[link widoczny dla zalogowanych], GM's director of universal battery systems. "You can move many more heat, and move it much more uniformly."
The Nissan Leaf promises 73 miles per electric charge, meantime the GM Volt gets 35 miles per charge, although it also has a backup gasoline engine for longer trips. But GM and Nissan are catching alter approaches to ensuring that the batteries in these cars last and remain safe. The access these batteries act over the next few years will suggest which approach is better, and could shape the design of hereafter electric cars and plug-in hybrids, which all major automakers have agreed. Some commentators say that Nissan's battery-pack design, which uses a relatively simple cooling system, could grant the batteries to overheat, decreasing the life of the battery and posing a safety concern.
GM and Nissan have also switched from a cylindrical shape for the batteries (the battery cells inside typical laptop packs look like large AA batteries) to a flat rectangular shape that saves space and also allows heat to escape better. Overheating can damage the batteries, decreasing their ability to store charge, and,[link widoczny dla zalogowanych], in some cases, can lead to a phenomenon called thermal runaway, when lifted temperatures outcome in chemical reactions that lead to but more heat, finally resulting in a fire.
Liquid cooling is the approximate chosen by Tesla Motors, which makes one electric sports motorcar using lithium-ion battery cells namely were originally designed because additional petitions. The cooling method ensures namely even if some compartments overheat and arrest fire, the rest wouldn't. In a recent proceeds shriek with investors,[link widoczny dla zalogowanych], Elon Musk, the CEO of Tesla Motors, criticized the Nissan chart, mentioning it could reason temperatures apt be "bring an end to ...the area," which could degrade battery performance.
But major differences emerge while you see at how GM and Nissan designed their battery packs—the accumulation of battery cells,[link widoczny dla zalogowanych], electronics, and temperature controls that make up the complete battery. The biggest difference is how the companies prefer to control the temperature of the packs. Nissan has opted for a simple design, using a fan to chilly its batteries. It says that the smooth shape of the battery cells makes added cooling unnecessary. GM's design is more complex. A liquid coolant carries fluid elapse the surface of every cell in the package and to a small radiator outdoor of the pack.
The Volt is likewise engineered to prop a definite amount of charge in keep when the car is new to aid maintain battery life. As the battery ages, some of this reserve capability will be unlocked, which ambition assist the car retain its electric scope over period. GM expects the capability of the battery to fade among 10 and 30 percentage during the life of the car (almost 8 to 10 years). Nissan has not said whether it will use a alike approach, but it has said that the Leaf's battery capacity will fade 30 percent in 10 annuals. It has also noted that exposure to peppery temperatures could diminish battery capacity faster.
The Electric Cooling Battery Test
Later this month, 2 fashionable electric cars—the GM Volt and the Nissan Leaf—will start appearing in eco-conscious driveways across the United States.
To residence these issues, GM and Nissan have made significant alterations to the lithium-ion batteries they're using. Instead of using lithium cobalt oxide —the substance favored in notebook batteries because of its high vigor density—as the electrode, they're using lithium manganese oxide,[link widoczny dla zalogowanych], which stores a relatively great amount of energy, merely is extra settled, in part due to the arrangement of its atoms. In a manganese-oxide electrode, atoms manner a three-dimensional structure that maintains its shape even for lithium ions shake in and out of the electrode for the battery is charged and dismissed. The less stable structure of conventional battery electrode materials tin be harmed as lithium ions migrate in and out, which shortens the profitable lifetime of a battery.
Because cold weather can limit the amount of charge a battery pack can store,[link widoczny dla zalogowanych], and cause damage to the battery, GM's pack also has a 1,800-watt resistive heater to keep the battery pack from getting too cold. Nissan recommends a cold weather pack that includes a battery heater,[link widoczny dla zalogowanych], but this doesn't come as criterion. And the adoption is not accessible for the 1st Leafs to come off of the convergence line, and it cannot be added to a car afterward. If the Leaf pack gets too cold, alternatively too hot, it enters a limited power mode, which restricts haste and altitude speed.
Wallace says liquid cooling was chosen to ensure that all of the cells in a pack are within two °C of an distinct. Along with preventing overcharging, "temperature control is the most essential handle you can turn in terms of improving battery life," he says.
In choosing lithium-ion over nickel-metal hydride,[link widoczny dla zalogowanych], GM and Nissan are taking a risk because such batteries haven't yet proved reliable in the demanding role of powering a car. Car batteries must persevere temperature extremes, coarse shakes, and perennial vibrations from the road, and must perform well for about a ten-year. In a few infrequent cases, lithium-ion batteries can overheat and catch fire, a problem that has required heavy recalls of some laptop batteries. The batteries needed for electric vehicles have to also store distant more energy—so a fire caused by automatic batteries could be especially risky.
Both GM and Nissan use lithium-ion batteries (a technology that's long been accustom in laptops and mobile calls) as disapproved to nickel-metal hydride batteries such as IBM ThinkPad R60 Battery, IBM ThinkPad T60 Battery and IBM ThinkPad X60 Battery, which have testified authentic in gas-electric hybrids such as the Toyota Prius, but which are bulky and cumbersome.
Another disadvantage of using lithium-ion batteries is that they rapidly lose their ability to hold charge. After a pair of years of use, it's not unusual for them to cache half as much power as they did when they were new. Automakers ambition car batteries that will final for the life of a vehicle—about eight to 15 years.

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