What is the reason for the three-dimensional lithium ion battery becomes a power battery?

　　Author ：Iflowpower – எடுத்துச் செல்லக்கூடிய மின் நிலைய சப்ளையர்

Safety is the heavy priority Wang Shihu said: The safety of the lithium-ion battery is not valued, the three-dimensional lithium-ion battery is characterized by large energy density, the voltage is higher, so the same weight battery pack battery capacity is larger, the distance of the car runs That is farther, speed can be faster. However, the weakness is that the stability is poor, if the internal short circuit or the positive material, there will be an open fire. Therefore, there are general 18650 batteries that have a steel shell protection.

Since Tesla's battery pack is complicated by the 18650 battery of more than 7,000 pieces, although Tesla is protected for the battery pack, it is extremely In the collision accident, there is still a hidden danger. The lithium phosphate ion battery is stable, the battery board is in the puncture, the short circuit will not explode burning, and the high temperature of 350 ¡ã C will not be fire (the three yuan lithium ion battery is can't hold at 180-250 ¡ã C). Therefore, on the safety performance, the lithium iron phosphate ion battery is slightly won.

Wang Shihu said: It is precisely because of such a safety hazard in terms of three yuan lithium materials, so manufacturers have also strive to inhibit the circumstances. According to the characteristics of the three-dimensional lithium material, Anhui Chunzhi Lithium is overcharged protection (OVP), Over-Protection (UVP), Oversic (OTP), overcurrent protection (OCP). A lot of effort.

The reason why lithium battery is confident is because we have a set of battery management systems that can better manage more active ternary lithium ion batteries. Of course, with more and more battery companies, the vehicle enterprises also have professional battery management companies in this category, and more companies can also achieve excellent battery management and greatly improve security. Here, it has to be said that the leadership of the relevant industry is also very clear.

On March 1, 2017, the four commissions of the Central Committee were invested in the "Measures for the Development Action of the Automobile Power Lithium Ion Battery Industry" clearly pointed out that one of the key development goals will be improved in the future. The following three points are the focus: 1. By 2020, the lithium-ion power lithium-ion battery monomer is more than 300Wh / kg than energy; the system is more than 260Wh / kg than energy; the cost is less than 1 yuan / watt; use the environment to -30 ¡ã C To 55 ¡ã C; 3C charging capabilities.

2. By 2025, the monomer is 500Wh / kg. 3.

Strive to achieve a single battery 350WH / kg, the industrialization of lithium-ion battery products of 260WH / kg, the use of vehicle. In fact, it is because of this direction of development, the spring of the three-yuan lithium-ion battery is really, because lithium iron phosphate can break through the single energy density, and the potential of the three-dimensional lithium ion battery is not Plenty of excavation. Question Wang Shihu on the life of the battery life, the life of the lithium-ion battery, the theoretical life of the ternary lithium-ion battery is the 2000 charge and discharge cycle, but in actual use, when 900 charge and discharge cycles, the battery The capacity is basically attenuated to 55%.

That is to say, only half of the original mileage can only be ran. However, if each battery charge and discharge is controlled in a cycle of 0% -50% or 25% -75%, combined with the excellent battery management system, even after 3,000 charge and discharge cycles, the battery capacity can basically Can be kept about 70%. The lithium phosphate ion battery cycle life is also more than 2,000 times, standard charging (5 hours), can reach 2000 cycles.

However, the lithium iron phosphate ion battery has a fatal disadvantage, that is, the low temperature performance is poor, even if the nanochemical and carbon cladding are not dealt with this problem. Research statement, a battery with a capacity of 3500mAh, if it works in the -10 ¡ã C environment, if there is less than 100 charge and discharge circulation, the amount of electricity will be drastically attenuated to 500mAh, basically scrapped. So in the north, this battery is really worr.