Lithium iron phosphate batteries: refers to the use of lithium iron phosphate as the anode material of lithium ion batteries. Its characteristic is do not contain the valuable elements such as cobalt, raw material prices are low and phosphor, iron exists in the earth‘s resources abundant, there would be no problem of feeding. Its working voltage (3.2 V), moderate large capacitance under unit weight (170 mah/g), high discharge power, can fast charge, long cycle life, high stability under high temperature and high temperature environment.
Advantages compared to the more common on the market and cobalt acid lithium manganese acid lithium batteries, lithium iron phosphate batteries at least has the following five advantages: higher safety, longer service life, does not contain any heavy metals and rare metals (low) cost of raw materials, support rapid charging, wide working temperature range.
Disadvantages of lithium iron phosphate has some defects on the performance, such as low tap density and compaction density, leading to a lower energy density of lithium ion batteries; The preparation of material cost and battery manufacturing cost is higher, battery low yield, poor consistency; Poor product consistency; Intellectual property rights.
The ternary polymer lithium battery: the anode materials using nickel cobalt manganese acid lithium (Li (NiCoMn) O2) ternary positive electrode material of lithium battery. According to tsinghua university ming-gao ouyang explains: the survey of "three yuan" referred to in the materials, refers to the positive electrode is 3 yuan, the anode is graphite is usually "three yuan power battery". In practical application in the research and development, and three yuan is a kind of positive, negative is lithium titanate, commonly referred to as "lithium titanate", its performance is safety, long service life, does not belong to common says "ternary material."
Advantages of ternary lithium battery energy density is high, the cycle performance is better than normal cobalt acid lithium. At present, as incremental improvements were made in the formulation and perfect structure, nominal voltage of battery is 3.7 V, on the capacity has been reached or exceed cobalt acid lithium battery level.
Faults ternary material power lithium batteries are mainly aluminum nickel and cobalt acid lithium batteries, nickel cobalt manganese acid lithium battery, etc., due to the high temperature structure of the aluminum nickel and cobalt is not stable, lead to high temperature and poor safety, and high pH make the monomer easily bilge gas, causing danger, the cost is higher.
Takeaway: in contrast, the ternary polymer lithium battery indeed have a more superior to the characteristics of lithium iron phosphate batteries, but why it‘s development by the obstacles? The key of the development of new energy vehicles, also is the key to haunt the mobile digital products, the development of the battery. How in the case of safety guarantee battery technology can satisfy the growing consumer demand, is not only the automotive related industry of science and technology personnel, or the pursuit of scientific research workers in all areas
Said to buy new energy vehicles, may is most consumers remember the first time the "preferential policy", although it is a bit awkward but it is quite true. In the domestic sales environment, new energy vehicles to open the situation, not just because of the sense of "environmental protection" such a long way. New energy vehicles on the price and the maintenance cost advantage is indeed attracted most of the present stage still is given priority to with transport costs of the love of consumers.
However the footsteps of some consumers may for some reason a temporary stop to the curiosity of new energy vehicles, because how much will be the new energy car events concerned of various kinds of spontaneous combustion. This is where the author today why to write this article. Must know do not know the root of the new energy vehicles, energy module, and don‘t understand matters need to pay attention to in the process of use, and actually buy a ticking time bomb in the side and no different.
Lithium iron phosphate battery: mature but is not enough
Electrode materials for lithium iron phosphate is the safety of lithium ion battery cathode material, combined with its cycle life reached more than 2000 times, the standard charging rate (5 hours) to use, can achieve the cyclical characteristics of 2000 times, coupled with the industry mature and technology threshold and the decline in the price, make many manufacturers for a variety of factors to consider using lithium iron phosphate batteries. The rise of new energy vehicles, so to speak, and lithium iron phosphate batteries are not or points.
Lithium iron phosphate batteries, however, there is a fatal weakness, that is the low temperature performance is poorer, even if the nano and carbon coating to solve this problem. Research has shown that a capacity of 3500 mah battery, if working in a - 10 ℃ environment, after less than 100 times charging and discharging cycle, power attenuation sharply to 500 mah, basic is discarded. This to China‘s vast, low temperature in winter is more comprehensive, the state of the union is not a good thing indeed.
In addition, the preparation of material cost and manufacturing cost is higher, batteries battery low yield, poor consistency, it also lead to a lot of pure electric vehicle battery life does not reach the nominal value of important reasons. Therefore, we can see that many of the nation‘s new energy vehicles (both electric and hybrid electric), or are some of the new energy vehicles is cheap, will choose the lithium iron phosphate battery for different reasons. The lithium iron phosphate battery, as it were, to use, the new energy automobile production floor and promotion, has an indelible based role.
In contrast, the ternary polymer lithium battery indeed have a more superior to the characteristics of lithium iron phosphate batteries, but why it‘s development by the block? Ternary polymer lithium battery is correct material using nickel cobalt manganese acid lithium (Li (NiCoMn) O2) ternary positive electrode material of lithium battery, the ternary composite cathode material precursor products, is the cobalt nickel salt, salt, manganese salt as raw materials, in the proportion of nickel cobalt manganese can according to the actual need to adjust. The ternary lithium battery energy density is bigger, but security is often suspect.
Is there such a reason is that even if the two materials will be in when you arrive at a certain temperature decomposition, ternary lithium materials can occur in the lower 200 degrees decomposition, and lithium iron phosphate material is around 800 degrees. And chemical reaction of the ternary lithium materials more intense, can release oxygen, under the effect of high temperature electrolyte rapid combustion, a chain reaction. Say simply, it is the ternary lithium material than lithium iron phosphate material more easy to catch fire. But it is important to note that we mentioned is the material, rather than batteries has become a finished product.
Because of the ternary lithium materials have such security hidden danger, so the manufacturer also in efforts to curb the direction of the accident. According to the properties of the ternary lithium materials easily pyrolysis, manufacturers (OVP) in the overcharge protection, discharge protection (UVP), over temperature protection (OTP), the over-current protection (OCP) composition among the link will be under a lot of kung fu. So more spontaneous combustion is should consider whether the function of the manufacturer in this a few link in place, rather than simply isolate.
So the usage of these two kinds of battery now is how? Let‘s focus on a set of data. Last November, lithium iron phosphate battery electric bus installed capacity up to 64.9%, the ternary lithium battery installed capacity is only 27.6%. On the contrary, in the pure electric passenger car market, the ternary lithium battery installed capacity of more than 76% in November last year.
It can be seen that the ternary lithium battery energy density greater preponderance, should be to for future car new energy storage device. Now related security incidents in the popularization of new energy vehicles is still in its infancy, is a good thing. A lot of new energy vehicles related businesses in order to be able to seize market and obtain the double goal of policy support, to broaden the technical requirements, mass production can not stand the repeated use of the energy components for a long time. Car work environment is harsh, use these parts for a long time, the reason of safety accidents is greatly increased.
So we can think in China ministry of industry and information technology on electric vehicle c equipment department chief priests published a picture of wood for three yuan bus to evaluate the safety performance of lithium-ion batteries, is interested in from the relevant state department on a standard definition of policy, to promote the industry standard. Both to consumers and manufacturers, has a very positive significance in the future. So there‘s no need for online one-sided see ternary lithium battery safety accidents can message material is danger, the key lies in how to firmly in control.
Different types of new energy car battery: unified requirements
Said these batteries, the author thinks that in the case of new energy vehicles, also need to with all of you a brief introduction of the role of the battery in the vehicle. Consumers buy pure electric vehicles, after all, still in the minority, more friends concern is a hybrid car. And hybrid cars can be divided into three types: strictly ordinary hybrid vehicles, plug-in hybrids and a hybrid cars.
The arrangement of the above three kinds of car battery capacity since the childhood was just ordinary hybrid < plug-in hybrid cars increase program or less a hybrid car. Ordinary hybrid non-rechargeable batteries, battery used to start and throttle state; Plug-in hybrid car batteries in ordinary enlarged capacity on the basis of a hybrid car batteries and rechargeable, have better speed and fuel economy ability; And increase the program used to drive the motor power hybrid engine, more inclined to pure electric vehicles.
The advantages and disadvantages of each three hybrid models in the main in the present stage is to ordinary hybrid and plug-in hybrid. Just because of three kinds of hybrid traits are for battery life and working environment in common, so either buy what model of hybrid cars, consumers have to pay more attention to the related parameters, such as battery material, use the environment and the best working state, etc. At the same time, manufacturers should also in the design process strictly control the battery quality and related security Settings, ensure the safety of the use of high efficiency.
Is the key to the development of new energy vehicles, whether to use the experience to rival or even beyond the traditional internal combustion engine car, at the same time in the link of purchase and after-sales whether has the advantage of better. In my opinion, the key of the development of new energy vehicles, also is the key to haunt the mobile digital products, the development of the battery. How in the case of safety guarantee battery technology can satisfy the growing consumer demand, is not only the automotive related industry of science and technology personnel, or the pursuit of scientific research workers in all areas.