Last chapel on Xiaojiang go be versed in grind the courtyard had a visit, subject matter is " the lithium ion batteries that won't explode " (guess filmy horn a bad shot XD) . Telling nevertheless how and stop before lithium ion batteries explodes, let us understand the principle of lithium ion batteries first, and why it can explode!
Why to use lithium ion cell?
relatively charge phyleticly at other batteries, lithium ion batteries has a lot of advantages, this among them a the most important, it is its energy density. The electrode of lithium ion batteries is the compound that use lithium and black lead commonly (pure carbon) be formed, both is very light material, at the same time lithium also is the element with a very strong reactivity, because this atomic bolts,more energy can be deposited in the knot. This is both addition, mean charge in what have in batteries, want to have the word of same harbour n, lithium ion batteries is the lightest, suit the vade mecum such as camera of report of mobile phone, pen, number to taste use. In addition, lithium ion does not have memory effect, that is to say lithium ion batteries need not put electric power first smooth ability recharge, and harbour n also won't decrease too quickly, about every month reduces the electric power of 0.1% (calculate on the demand that protects loop also just 5% , nickel hydrogen batteries about every month decreases 20% ) . Finally, it is OK still all previous classics hundreds charge discharge, still full of vim and vigour.
Batteries of Dan Li ion is faulty also. Among them a the mainest, the total harbour electric power that is it (the biggest n) meeting as leave factory time increases and decrease- - no matter you are used need not lithium ion batteries, leave factory the electric power of the biggest labor of the batteries after year can reduce 2~3 considerably, cannot use even, accordingly " bought putting " it is full of prunes practice. Next, lithium ion batteries very be afraid of heat, the effect that n of the biggest on the environment of high temperature labor reduces can be quickened, the meeting is again compensatory at the back of this part. Moreover, lithium ion batteries also has been afraid of discharge, one but discharge exceeds a certain level, electric power also may be filled again do not go in. Of course, lithium ion batteries still has the risk that can explode, everybody knows this.
Why can lithium ion batteries explode? This wants to be mentioned from its chemistry. . . The chemistry of lithium ion batteries
What do not tell as far as possible here is too thorough (it is actually also already not was to know Orz completely oneself) , but simple for, lithium ion batteries mixes all charging batteries is same, have an anode material and stuff of a negative pole, here positive electrode material is it is lithium cobaltic oxygen normally (LiCoO2) , and negative pole material has a lot of kinds, the commonnest black lead (carbon) . The lithium ion in cobaltic oxygen of the lithium when charging can have swum the electrolyte among, adherent go up in negative pole, and discharge (on graph) when it is contrary, swim from the carbon of negative pole lithium cobaltic oxygen this a side.
In the lithium ion batteries that is in to be negative pole with black lead, it is to use cobaltic oxygen of a lithium, an a disjunctive content of electrolyte, black lead is a group, a group of a group happen frequently come. In mobile phone batteries the sort of thin model in batteries, a such one layer happen frequently comes inside, and the cylinder of material roll into this one is normally in pen report shape, become like 3 batteries in that way thing. In lithium ion batteries, those who contain the biggest risk is not two electrode, however the organic electrolyte dissolvent among, with flammable ether kind most. When batteries because when any reason short circuit, the energy inside batteries can be in short time is released with hot form, ignite these aether as solvent kind, cause explosion.
Ion of the lithium when discharging too is met and lithium cobaltic oxygen produces reaction directly, produce lithia and oxidation cobalt. This reaction is not reversible, batteries is equal to the lithium ion that discharges too so submitted an expense account.
Does lithium ion batteries explode very easily?
Xiaojiang grinds in labour the experience that the courtyard gains is: " how to explode so hard! " grind in labour courtyard, they installed a machine, with broach of piercing flat state thin model batteries, basically need need is new, it is dangerous that the cell that fills full report just has the biggest burst, if use,live the cell of period of time only, not only the biggest voltage can be reduced greatly, and inside use data also is met " passivation " , become so not easy reaction. We prepared one pile old batteries to prepare to want to explode a satisfy a craving, doing not have those who think of is, not only all old batteries did not explode, even brand-new batteries not likely explodes every. It is good that this says to buy used batteries to be not done safer? XD
But explosion is one and the same, we still saw very terrible temperature from the thermometer on bougie, internal temperature often is in after batteries short circuit 100 degrees of above, most propbably is so very hot a thing is put in trousers pocket still is cannot comfortable!
What safety precaution does lithium ion batteries have?
To avoid overheat of lithium ion batteries, explode even, contemporary lithium ion batteries is built-in the mechanism that a lot of ego protect. Above all, batteries of every lithium ion (or in the example in pen report, group of whole group batteries) built-in chip of a control, this control chip is met the voltage of monitoring batteries (the word of batteries group, meeting monitoring among them the individual voltage of every batteries) with temperature, exceed the range of set, chip can cut off the power automatically. In addition, every batteries still can design steam vent, the gas that because high temperature arises,allows is discharged smoothly, unapt accumulate generation explosion.
These safeguard are enough for the batteries of harm to doing not have entity, but if be to be destroyed (for example by puncture) how does lithium battery do? This is labour grinds the strong point of the STOBA batteries of courtyard new research and development. STOBA batteries joined a kind inside electrolyte " the high polymer material of Nai rice class " , when be heated, assemble of material of this kind of high polymer closes to have the film that isolates the effect into a kind, stop the flow of lithium ion, cut off cruel the likelihood that the short circuit battery that take continues to increase pyroelectricity pool. This kind of technology prevents batteries explosion not only, also prevented cell likelihood the danger of overheat, major the test that we see, temperature did not exceed centigrade 60 degrees- - still can iron, but do not have ignition at least all round the danger of combustible.
How does lithium ion batteries maintain?
The first the most important principle: Do not buy batteries to come back to reserve! Had said before, no matter you are using it, the n of lithium battery harbour that leave factory can be reduced gradually, bought unused batteries to be wasted namely really accordingly. Manage together, special attention also wants when buying new battery its date of production, if leave factory,exceed batteries of a year, n of very possible harbour remnant is brand-new the half of batteries!
Additionally two affect the factor that harbour n reduces, it is temperature, 2 it is batteries is filled much fuller. No matter what you do (or what to do) , the total harbour n of lithium battery is to be in ceaselessly those who drop, but fill high blandly full the speed that can drop quickly however. Because this buys a so not enthusiastic pen electricity, have openly help to fecundity not only, of the harbour n to slow down batteries reducing also is the help is very great. Additional, if the computer has relevant set, fill cell full the rate that can lower harbour n decreases for the half- - meaning if fill cell every time,arrive namely full, if the computer that can run 4 hours originally after a year can run 2 hours only, that fills cell only every time full, the computer still can run 3 hours after a year. Xiaojiang knows Panasonic and Thinkpad have such set only, do not know to still have other mill plate to have?
For more details, visit http://en.wikipedia.org/wiki/Lithium-ion_battery
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