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　　Graphene battery was popular in the battery industry in the past few years, but it finally fell silent. The main stream battery in the market is still lithium battery. Which is better, graphene battery or lithium battery? We should compare their own data characteristics and the advantages and disadvantages of the market application to distinguish their quality.

　　1. Advantages and disadvantages of graphene battery

　　Graphene battery: graphene battery is a kind of honeycomb flat film composed of carbon atoms by SP2 hybrid method. It is a quasi two-dimensional data with only one atomic layer thickness, so it is also called single atomic layer graphite. A new energy battery has been developed based on the fast shuttle motion of lithium ion between graphene surface and electrode.

　　(1) Advantages of graphene battery:

　　1) The storage capacity is three times of the best products in the market. The specific energy of a lithium battery (whichever is the most advanced) is 180wh / kg, while that of a graphene battery is more than 600wh kg.

　　2) The electric vehicle powered by this battery can travel up to 1000 kilometers, and its charging time is less than 8 minutes.

　　3) Long service life. Its service life is four times that of traditional hydrogenated battery and twice that of lithium battery.

　　4） Light weight. Graphene's properties allow the weight of the battery to be reduced by half of that of a conventional battery, which can increase the power of the machine on which the battery is loaded.

　　5) Graphene has more advantages than traditional batteries. In terms of service life, its service life is twice that of lithium battery and four times that of hydrogenated battery.

　　6) It's faster to charge, and it's more economical than lithium battery at high temperature.

　　(2) Defects of graphene battery:

　　1) At present, the graphite has not reached the practical stage, and there is a long way to go before mass production.

　　2) These graphene batteries in the market are not pure graphene batteries either. They are only based on lithium batteries and doped with some graphene related technologies. Compared with traditional lithium batteries, the performance improvement brought by them is only a little bit. In addition, the cost of graphene is very high, and its manufacturing process is also very high. The manufacturing process of graphene battery is still not sophisticated enough, and now it is only in the laboratory stage, it can not reach the point of mass production.

　　3) Incompatible process characteristics. It is that graphene is larger than the surface product, which will bring a lot of technological problems to the existing processes such as dispersion and homogenization of lithium-ion batteries. If the battery factory adjustment process will be exhausted, and there is not enough profit space driven by breakthrough performance indicators, who is willing to use this technology? Graphene surface properties are greatly affected by chemical conditions, batch stability, cycle life and many other problems, now it can not meet the detailed requirements of lithium battery production.

　　2. Advantages and disadvantages of lithium battery

　　(1) Advantages of lithium battery

　　1) The energy density is high, the bulk energy density and mass energy density can reach 450 w.h/dm3 and 150 w.h/kg respectively, and they are still improving.

　　2) The average output voltage is high (about 3.6V), which is three times of Ni Cd and Ni l batteries.

　　3) High output power.

　　4) Self discharge is small, less than 10% per month, less than half of Ni Cd and Ni ml.

　　5) Without the memory effect of Ni Cd and Ni MH batteries, the cycle performance is superior.

　　6) It can charge and discharge quickly, and the capacity of 1C can reach more than 80% of the nominal capacity.

　　7) The charging power is high, basically 100% after the first cycle.

　　8) With the improvement of electrolytes and positive electrodes, it is hoped that the working temperature range is wide, ranging from - 30 ℃ to - 45 ℃

　　-40 ~ + 70 ℃, low temperature may be widened to - 60 ℃.

　　9) No maintenance required.

　　10) Friendly to the environment, called green battery.

　　11) It has a long service life and can be charged and discharged more than 900 times with 100% DOD. When shallow depth (30% DoD) is selected for charging and discharging, the number of cycles has exceeded 5000.

　　(2) Lithium battery defect

　　1) With the development of positive technology, LiMn204 and LiFeP04 can be selected as positive electrodes, which is expected to greatly reduce the cost of lithium-ion batteries;

　　2) Special maintenance circuit must be provided to avoid over charging or over discharging;

　　3) Due to the poor compatibility with general batteries, lithium-ion batteries can only be used as substitutes when three general batteries (3.6V) are used.

　　Summary: according to the above conditions, from the perspective of current situation, from the perspective of R & D technology sophistication, manufacturing cost and market economic benefits, lithium battery has more advantages than graphene battery.

　　Zhongshan lithium battery manufacturer http://www.nekow.cn/