Foldable lithium ion battery | Oriented carbon nanotube film replaces traditional metal current collector

Recently, the carbon nanomaterials team of the School of Materials Science and Engineering of Jiangxi University of Science and Technology published a paper entitled "Engineering the Surface/interface of Horizontally Oriented Carbon Nanotube Macrofilm for Foldable Lithium-ion" in the international top journal Advanced Energy Materials (impact factor 21.875). Battery withstanding Variable Weather'. Professor Wu Ziping from our school and Professor Xia Baoyu from Huazhong University of Science and Technology are the authors of the paper. Jiangxi University of Science and Technology is the first unit of the thesis. Liu Ting, the master student of our school, Zhang Ming is the first author of the work. .

Lithium-ion batteries (LIBs) are currently the most common energy storage devices. With the rise of wearable electronic devices, the flexibility of batteries is the basis for device wearability, and flexible current collectors are the key to flexibility of LIBs. Current LIBs The fluid is mainly copper foil and aluminum foil, which limits the deformability of the battery. In addition, the battery will fluctuate with the electrochemical performance as the weather changes. For example, in cold weather, the battery even stops working. This is the wearable electronic device that wears on the outside. A real problem that must be faced, but it is rarely noticed.

The work was carried out on paper as a matrix, and the scaled carbon nanotube film (HUCNMs) was scaled up by surface interface modification. The obtained HUCNMs area was ~1800 mm×1000 mm, which was used as the positive and negative current collector of LIBs, and LIBs showed Excellent flexibility, electrochemical stability and rate performance; single-layer full battery capacity higher than 700 mAh, specific capacity 160 mAh/g, battery is stable at different temperatures (-40~70 °C) and low pressure The electrochemical performance shows excellent weather resistance. In addition, the research group recently developed a flexible cable-type battery based on carbon nanotubes, published in Small (impact factor 9.598, DOI: 10.1002/smll.201800414), the resulting battery The volumetric energy density is 215 mWh /cm3, which is more than 7 times the highest value reported in the existing literature. These demonstrate the great potential of carbon nanotubes in the field of flexible energy storage.