Put the battery on the body, Chinese scientists achieve new breakthroughs in fiber lithium-ion batteries

No need to bring charger and mobile power when you go out，Through clothes，You can wirelessly charge your phone。This scene in people’s imagination is gradually becoming a reality。
recently，The main journal of "Nature" published a study by the team of Professor Huisheng Peng from the Department of Polymer Science of Fudan University。The research system reveals the variation of the internal resistance of the fiber lithium-ion battery with the length，Effectively solve the problem of interface stability between active materials and fiber electrodes，Continuously build a new type of fiber polymer lithium ion battery with good safety and comprehensive electrochemical performance。
According to the results of this research，Fiber polymer lithium ion battery with a length of 1 meter，Can be a smart phone、wristband、Wearable electronic devices such as heart rate monitors provide continuous and effective power supply for a long time。Simultaneously，The battery has good cycle stability，After 500 cycles，The battery capacity retention rate still reaches 90.5%；In the case of a radius of curvature of 1 cm，After bending the battery 100,000 times，Its capacity retention rate is still greater than 80%。

Show picture of the concept of future wearable battery fabric (Photo courtesy of Fudan University)

Energy storage devices represented by lithium-ion batteries，Known as the "heart" of modern electronic equipment。The Peng Huisheng team proposed and realized a new type of fiber lithium-ion battery in 2013，Provides a new path for the energy supply of wearable devices such as smart electronic fabrics。However，Research on fiber lithium-ion batteries has faced a key challenge for many years，That is, the mature production system for bulk lithium-ion batteries is difficult to apply to fiber lithium-ion batteries，The international research on the continuous preparation of fiber lithium batteries is almost blank.，The length of the fiber lithium-ion battery reported so far is in the centimeter scale。
"Fiber lithium-ion battery is like wool，To knit into a rechargeable sweater，You have to make sure that you have enough wool。"Peng Huisheng team members found，To achieve the continuous construction of fiber lithium-ion batteries，It is necessary to clarify the relationship between the internal resistance and length of the fiber battery from the source。By extensively experimenting with fiber current collector materials with different electrical characteristics，They finally revealed that the internal resistance of the fiber lithium-ion battery decreases first and then gradually stabilizes with the increase in length.，Provides strong theoretical support for the continuous construction of fiber lithium-ion batteries。
on the basis of，It is also necessary to realize the efficient continuous preparation of high-efficiency load fiber lithium-ion battery active materials。"The classic method is flat coating，However, coating on the fiber surface is easy to produce uneven beaded structure，Very bad for battery performance and stability。"team member、Said He Jiqing, a doctoral student in the Department of Polymer Science, Fudan University。
to this end，The team develops a new method，By adjusting the composition and adhesion of the positive and negative active materials，Effectively solve the problem of interface stability between polymer composite active materials and conductive fiber current collectors，Got a high load、Uniform coating and highly matched positive、Anode fiber electrode material。Subsequently，The team has successively carried out methodological research on continuous battery assembly and packaging，Finally, the continuous and stable preparation of high-performance fiber polymer lithium-ion batteries is realized。

Schematic diagram of wearable battery fabric Photo courtesy of Fudan University

According to reports，The team adopted the textile method，High-performance large-area battery fabrics have been obtained。Integrate battery fabric and wireless charging transmitter，Safe、Stable wireless charging of smartphones。
"Fiber lithium polymer ion batteries have shown broad application prospects，But compared with the energy density of flat batteries commonly used in life，This battery has a lot of room for improvement。also，Still need more advanced weaving technology，Efficiently knit the battery into various clothes，Make people wear more comfortable、Beautiful。"Peng Huisheng said。