| In lithium-ion battery research and development, to fabricate high power batteries for electric vehicle and other devices draw a lot of attentions. To reduce the cost, improve the security and cycle performAnce under high temperature (55℃, HT cycle performAnce) is key problem for the aim. Now many kinds of cathode materials that have good security and HT cycle performAnce have been studied. However, due to the complex technics and the use of Co, the cost still is a big problem. So this study is based on simple technics and non- cobalt.Present work focus on the following to direction: 1. Synthesize a novel mAterial with a diameter below 1um and without cobalt. 2. Fabricate the simulant cells using this new cathode mAterial obtained by the new method and to measure and investigate the discharge capacity and HT cycle performance. In our work, we use co-precipitation reaction and a molten salt method obtain the Li(Li0.15Ni0.21Fe0.21Mn0.45)O2 particles around 500nm. Scanning electron microscope is used to study the morphology of the particles. ICP-AES is used to analyse the component. And XRD is used to measure the structure of the materials and the phase transformation during the cycleing. It is proved that the novel method was a potential method to be used in industry.This cathode material shows good HT cycle performance under 55℃.After 500 cycles under 1C(150mA/g), the capacity reduce from 101.1 mAh/g to 63.4mAh/g (63.7% left). After 600cycles under 2C (300mA/g), the initial capacity is 86.60 mAh/g, and fades to less than 80% after 428 cycles. The self-discharge after aging at 55℃and 7 days is just 14.98%.Other kinds of cathodes are also synthesized and primary research of the shape contral has been done.
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