BYD competes against Tesla on lithium battery performance

In a few days ago, media released two articles about Tesla battery pack partial dismantling. Tesla ultimate dismantling-Tesla battery reveals for the first time: (1) Tesla ultimate dismantling- Tesla battery pack uncensored for the first time (2) A lot of electric fans discusses this event, including the comments by professionals and the lithium battery industry practitioners.

But at home whenever someone discusses Tesla, someone likes to another new energy automobile manufacturer comparison with BYD.

Comments are divided into two groups, who backed the Tesla, those who backed BYD.

Given you so concerned about the home depot, the author here also does the simple analysis. In China all the two most familiar with the electric car brand is BYD and Tesla, comparing with both do have a point. We choose the same e6 around 60 kWh of electricity and tesla ModelS60 comparisons. The e6 offer 30-370000, the domestic price to about 20-250000; Tesla ModelS 60kWh version of the United States offer $62400 (RMB 380000), home to 648000.

The e6 in October 2011, Tesla ModelS delivered in June 2012 formally. Both time to market by more than half a year, but Tesla ModelS listed before have electric cars Roadster technology accumulation, and BYD is not. As for appearance and interior, many things, everybody will understand.

BYD is using iron phosphate lithium-ion batteries, and Tesla is using cobalt acid lithium18650 battery. A single from the battery safety point of view, BYD dominant, Tesla dominant theory is battery capacity. BYD maximum range is 300 km, TeslaModelS60kWh range of 390 km.

For the attention of battery fire accident, is very much a part of the review of your web site. Finish see comments, first have to admire the Chinese netizens' strength, but this shows all of the electric car safety concerns. But in terms of vehicle safety, we now see the data and results, Tesla does seem to be more perfect, at least the Tesla didn't happen because of a fiery death accident. In the previous article believe you also see the Tesla in the battery pack design, poor security cobalt acid lithium batteries did tight security processing, they give each battery is connected to the two fuses, thus the security of the battery to a relatively high level. Anyway, we see is the final result.

In addition to the battery fire, battery attenuation is also the focus of the debate., according to the measured before each big auto media after running 500000 km e6 taxis in 80% of the remaining battery capacity; After running 160000 kilometers, according to the report Roadster in 80% - 80% of the remaining battery capacity, the ModelS have not seen the relevant report at present, but the actual attenuation should move closer and Roadster. For the authenticity of the data in this not do comment, in terms of the theory of battery characteristics, BYD used iron phosphate lithium-ion battery batteries in terms of cycle life really bit tesla use cobalt acid lithium batteries is better. But BYD taxi company inati on taxi company is by the Shenzhen bus group co., LTD. And BYD auto co., LTD., jointly established by the battery should be conducted by BYD engineer maintenance over a long period of time.

As far as we know, the BYD's battery is lifetime warranty, Tesla is 8 years unlimited mileage warranty. On this view, the BYD battery is very confident in me.

What is 18650?

We also know in the comments that many readers know little about related knowledge of lithium-ion batteries.

One of the best comment is "this battery haven't digital works, section more than six section, Tesla finished with the remote control and then use!" See this review, the author could, is so funny.

Never expected readers can't tell anyone18650 lithium batteries5 and the battery. The same fallacy to Mr. Lang recording program is also an issue of this year. So we have to give readers basic knowledge of add.

Type 18650 lithium battery is commonly used in electronic products, its model defined rules in 18 refers to the battery to 18 mm in diameter, refers to the cell length is 65 mm, 65 0 refers to the cylindrical shape the battery. At ordinary times life common type and 26650 type 26650 lithium battery and lithium battery (the same size 5 batteries), the large size and even a 42120 model.

Car battery insulation

Of course, there are also some paragraphs a slightly better in the reader's readers, CARES about the car under the condition of cold working conditions.

We need to explain here, cobalt acid lithium battery standard discharge temperature is 20 ℃ to 60 ℃. Needless to say, so summer in hot weather. As for the low temperature, the condition is workable? According to people familiar with the Tesla battery solution in - 50 ℃ above the freezing point of water glycol (coolant) can work environment and, of course, this does not mean that in a - 50 ℃ environments directly start the vehicles on the road, but the first to use cold suite of battery heating (the temperature even gasoline car too hot a half a day to hit the road), transfer through the pump after cooling fluid heating to each section battery, when the battery temperature reaches 0 ~ 5 ℃ (lithium battery under low temperature fast), you can drive on the road.

Heat dissipation aluminum tube

In the comments I see a lot of people will be around tesla aluminum management solution for heat pipe, here I have to explain, this is definitely not the heat pipe.

The working principle of heat pipe is totally enclosed pipeline internal smoke into a negative state, filling the right amount of low boiling point liquid, when to produce temperature difference, the internal liquid will quickly evaporate and take away heat, and then in lower-end condensing temperature, again through the porous capillary material backflow, fast take away heat cycle.

And around the battery in Tesla first didn't smoke into the vacuum of aluminum tube, second is filled with liquid inside. Is this completely does not conform to the principle of heat pipe?

If the thermal conductivity aluminum tubes with heat pipes is workable? The answer must be no. Between first tesla's battery does not need to be so efficient heat conduction ability, imagine when there is a battery fails, a sharp rise in the temperature, battery before fusing fuse heat is taken away by heat pipe, the failure of the section of the battery will drive the whole battery pack speed to heat up, this is extremely dangerous. The second role is largely by the high thermal conductivity of aluminium tube liquid specific heat capacity of liquid on the battery insulation, prevent the battery's cells from overheating, and aluminum tube with rubber insulation between the cells in a certain extent also interrupts the effect of thermal conductivity of the aluminum tube. Moreover in a cold environment, also need to rely on heating cooling liquid lithium-ion batteries to the battery back up to working temperature.

To sum up the Tesla not using heat tube, and cannot heat pipe.

Battery protection

About Tesla battery protect part I see a lot of interesting comments.

About this question, in fact, last year the Tesla had several cars on the road encounter object impact damage battery protection shell, leading to the lithium battery fire accident. Although there are no casualties, still brought great impact to Tesla.

Tesla CEO elon musk said that after the accident they receive about ModelS of fires in various countries of the world's headlines even number more than 200000 the total number of accidents last year the United States., he said, for this case, the onboard computer will warn the user when the fire escape vehicle, even if the passengers had no time to escape, before the fire brigade arrived, they will still be under the protection of the safe, because the firewall between the battery and the passenger compartment is made up of steel and ceramic material filling.

Event yet, of course, since this march tesla production all cars will be equipped with a triple bottom protective layer. The first is a hollow round aluminum bar, decorate in front of the battery, when the road has approached the obstacles, can rise to change direction to prevent obstacles close to the battery. In addition, the aluminum bar to a certain extent also can absorb the impact of the obstacles. The second layer is a titanium plate, the material of the protective plate usually only inspecial and military applications to see, titanium plate can prevent damage of sensitive components are at the bottom of the before, after the most obstacles when a layer of protection will be deflection or pieces. As for the tiny fragments of individual are still intact, is 100% in the third layer, there is solid aluminium extrusion and into this layer, through the layer to absorb impact energy, the obstacles will not affect the battery.

Although don't like the comments said that tesla's chassis has a bulletproof shield, but since this installed at the bottom of the shield, we temporarily haven't received of fire accidents caused by a breakdown at the bottom of the battery.

Toyota FCV is: fuel cells "shooting" lithium batteries

On June 25, Toyota has revealed its fuel cell car design of FCV, and announced the FCV sales in Japan will be the beginning of the year, in the United States and Europe will release in the summer of 2015, in Japan's price is 7 million yuan, equivalent to about 420000 yuan, or about $68000.

Compared with Toyota's claim that the price is not higher than the $50000 before the published price is on the high side, but don't forget, this is just a booking price, final price usually is lower than booking price. And, like zero-emission vehicles, subsidy policy is also not less, the Japanese government has drafted a schedule, through subsidies and tax breaks to support the development of fuel cell.

Phase than in 1991, Roger Lin developed the world's first used in automobile fuel cells, let all the car "sound and smell of water pipe", and fuel cell vehicles from FCHV - adv concept car, the FCV concept car to FCV production car, finally sprung.

About since the word has a new energy of fuel cell and lithium electric car direction, there is no break, up to the national government's energy strategy, use cost down to common people, the industry chain is yet to be perfect, infrastructure construction and the cost is the common enemy, so the people in the two camps are each have a stick to reason, if you are the wind I am sand, smell to the end of the world.

Although fuel cell and lithium electric cars are electricity instead of chemical energy, two different supply can let them the distinction that having an essence. In an instant by charging with hydrogen compared to ground. Even if cannot build charging station, pick up a transformation from the household power connector and barely can deal with, but it is not a literally anyone can fuel cell car from home out of hydrogenation cans.

Compared with the traditional cars, electric vehicles new parts lithium battery is the most worrying is safe and life problems. Most importantly, range anxiety or an incurable disease in a short time. And for a long time, the fuel cell car's biggest shortcoming is no PIC, no truth, no products, no end. Although rowling solve the problem of the crossover of the fuel cell, both hydrogen preparation, and storage, can't get like electricity flying off the shelves. Fuel cell vehicles, therefore, cannot like lithium electric cars, with the development of the original, can let the consumer to participate.

Another downside of the power supply mode is selected, to traditional power "compromise". Lithium electric cars of anxiety disorders can use a hybrid or extended range to compensate, but in the fuel cell car, let alone have to join the engine room, once the existence of the engine, for fuel cell vehicles and car companies, that is bright since the face act.

So, to start selling fuel-cell cars Toyota years was a landmark event. Range of FCV at about 700 kilometers, a hydrogen filling time is only 3 minutes, with the traditional cars, although the construction of filling stations still need big money, but enough long range that the density of filling stations do not have to too high, in California, for example, research suggests as long as 68 will be able to meet the requirements of fuel cell vehicles. In Japan have developed a portable hydrogen station, appearance looks are the combination of truck + container, the cost is greatly reduced.

Fuel cell car though pious covered face, but Toyota this conference is a flare, officially declared the fuel cell vehicles on the stage of lithium electric car equivalent, since then, fuel cell vehicles and lithium electric car joint face subsidies for infrastructure and policy, whose construction speed is faster, whose subsidies strength is stronger, who can get more market.

Fuel cell and lithium-ion battery compared the advantages and disadvantages

Someone on the Internet asking: "fuel cell relative to the lithium-ion battery what are the advantages and disadvantages?" The following answer from battery practitioners.

To compare the advantages and disadvantages, the premise is that under the precondition of the same application purpose.

Fuel cell and lithium battery as the first object are different but the same, and then to the comparative advantages and disadvantages for different applications.

Different ways of working: fuel cell chemical energy input, the output power; Lithium battery input power, output power. Therefore, the fuel cell is an energy conversion device, and lithium battery energy storage device (electricity).

The same discharge principle: fuel cell and lithium battery export electricity is not heating engine process, but the isothermal adiabatic process of electrochemical power and high efficiency.

advantage

1. When the boundary is the human society on earth, for the future energy structure adjustment, the significance of the fuel cell > : lithium-ion batteries in the fossil energy can most represent a share in one thousand two hundred, how to improve from fossil terminal useful work efficiency to consumption, and how to block a specific form of useful work and determine the corresponding primary energy structure, the key is energy conversion device (easy for people to analogy to the meaning of the industrial revolution of the steam engine) of the change, and the role of energy storage device is often to optimize energy use efficiency.

2. Especially when the boundaries are vehicle ground vehicles, fuel cell drive than lithium batteries is more likely to be similar to today's car formats: energy recovery within 3 minutes, up to more than 400 kilometers. Chemical reactions need oxidant, reductant (commonly known as the fuel) and reaction, fuel cell car only need to carry two things: fuel and reaction - fuel cell; Lithium battery cars will be expected to all three samples, and lithium battery in the oxidant, the reductant, deposit is close (current relies on hundred microns thick diaphragm) even if they don't work also has the self-discharge, and lithium battery for a life cycle tend to put a pale imitation, is not like a conventional car to each cycle will oil with dry, oil filling, so real when using travel distance theory but also in half. This is now the fuel cell car travel distance effectively can reach more than 600 kilometers, and lithium battery travel distance effective generally less than 100. Internal combustion engine vehicle fuel cell car is similar to natural gas, reaction sites and fuel can be physical isolation, fuel injection is a physical process, how fast can quickly - feels it, as long as the economy and recovery is a rechargeable lithium battery car energy process, namely the electrolytic reaction, the need to control or else there will be side effects occur, the fuel filling speed is restricted by the degree of technological progress.

Insufficient

1. When the boundary is portable electronic equipment, fuel cell as oxidizer, reductant, reaction separation, simplify the difficulty of the system integration is far greater than has been fully integrated lithium battery or other types of secondary batteries;

2. When the boundary is the grid uninterrupted backup, 2ns requirements of electronic equipment, fuel cell to the separation of oxidant and a reducing agent to the cell is almost impossible to achieve;

Industrialization: fuel cells have no products manufacturing, And lithium battery field power supply for portable electronic equipment has already formed the batch manufacturing. But in view of the car, neither formed products manufacturing, the common technical difficulty lies in how to adapt to the electrochemical reaction motor perceptual load dynamic demand.

Lithium battery cars are easy to bewitch, because now there has been a lithium battery industry, will be easier than fuel cell vehicles to replace the internal combustion engine car history position. The word fallacy: product development from customer requirement, didn't hear a lawn mower with an internal combustion engine through upgrading can achieve automotive internal combustion engine; Empirical cognition: battery cars, beginning in 1900, is the fourth wave of lithium-ion batteries, as if still won't be successful in this decade, it is a difficult thing.

The most let a person look forward to that: the fuel cell engine + lithium battery electric hybrid drive car formation, can 1) double efficiency;2) zero emissions vehicle;3) longevity and cost easy to reach;4) get rid of the single rely on the automobile for crude oil resources.

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