In the increasingly popular electric vehicles today, life will often see a variety of brands of various grades of electric vehicles, with the continuous extension of the product line, EV market segments, such as the recently released pure electric SUV, including the cloud Degree π1, Tesla model X, BYD Song and other models. The vast majority of consumers daily driving distance of less than 80km, but hope that the mileage can reach more than 500km, why pure electric or not applauded, the fundamental reason is because pure electric vehicle technology has not yet reached the expected progress, the most important Is the mileage can not meet the needs of users, charging speed catch up with the speed.

 Mention here is a concept of "mileage anxiety" refers to driving a car because of fear of sudden mental loss caused by mental pain or anxiety. So how to resolve mileage anxiety? Today, from the battery point of view to interpret the next.

 The most immediate solution to mileage anxiety is to increase the mileage of electric vehicles. The core is to increase the energy density of battery packs and single cells. The other is to do fast charge batteries, such as Toshiba's recently introduced super fast-charge titanium-niobium battery.

 How to solve mileage anxiety from a battery point of view

 We can see if the Tesla model S or model X 18650 battery is replaced by the latest 21700 battery, the battery life is increased: the battery capacity is estimated to be 30% increase, the volume of the 21700 is 46% larger than the 18650, Non-linearity with capacity and conservatively taken as 30% increase in battery capacity.

 Talk about how to resolve the anxiety of electric car mileage from the battery point of view

 At present, the mainstream power battery companies have exceeded the energy density of 180wh / kg, with a cloud of π1 carrying Bik 18650 cylindrical battery, for example, its energy density has been close to 250wh / kg. The following figure is the roadmap for the development of Bürk battery system.
 Talk about how to resolve the anxiety of electric car mileage from the battery point of view

 It can be seen from the above road map, in fact, want to improve the energy density or from the battery material work hard. Here are several important directions in detail about the battery energy density increase.

 positive electrode
 From the positive point of view, the current use of grams of high capacity Ni ternary material NCM622,811 or higher capacity large NCA material is the only way for battery companies.

 In addition, the development of high-voltage positive ternary materials will also have a significant effect on energy density. The following figure shows the energy density of different proportions of NCM ternary materials at different upper limit voltages in 20Ah flexible battery.
 Talk about how to resolve the anxiety of electric car mileage from the battery point of view

 At present, there are still some problems of high voltage system that are not solved, such as the impact on the cycle life. The following is a high Ni system after 600 cycles at different upper limit voltage capacity retention rate contrast. High-temperature cycle attenuation is more serious.
 Talk about how to resolve the anxiety of electric car mileage from the battery point of view

 Finally, I think it is very important that in the design of the cathode system should minimize the use of non-reactive substances such as binder, conductive carbon and so on. This requires auxiliary materials and other properties need to be further improved to reduce the amount, such as ultra-high adhesion of PVDF and SWCNT materials. With this, the ternary system loading can achieve the level of nearly 99%.