High Energy Density Solid State Storage Battery

Qingdao Energy Storage Institute has developed a large capacity of 6Ah solid ternary lithium battery. Solid-state battery does not fire and explosion, the safety performance is excellent, and the removal of the nail after the voltage has been restored, which once again highlights the solid electrolyte (solid electrolyte) Good self-repair performance and safety performance.

National "thirteen" plan to increase the new energy vehicles, especially the layout and planning of pure electric vehicles, and the healthy development of new energy vehicles is the key to power battery, solid-state battery is a new energy vehicle power battery effectively improve energy density while ensuring Safety of the only way, and comprehensive performance of the new solid-state electrolyte system is the key to the development of solid-state batteries. The current solid-solid interface contact resistance has been a big problem and obstacles to the development of solid-state battery bottlenecks one of the problems. How to reduce the solid-solid interface contact impedance has become a scientific and industrial research and development of hot and difficult.

Relying on the Qingdao Institute of Bioenergy and Processes of the Chinese Academy of Sciences, Qingdao Energy Storage Industrial Technology Research Institute has been committed to the development of high-performance solid-state battery key materials and solid-state interface solid-state battery repair and improvement work. The research team of the institute creatively put forward the design concept of "Rigid-flexible and Concurrent" polymer electrolyte, and innovatively constructed the composite electrolyte material system, and prepared a series of excellent solid polymer electrolyte system (Energy Storage Materials, 2016 , 5,139-; Journal of Materials Chemistry A, 2016, 4, 10070), the effective solution to the polymer electrolyte performance can not take into account the problem, the development of new solid electrolyte key material system.

In response to the bottleneck in solid-state interface impedance in the development of solid-state batteries, the team members of the Energy Storage Institute started with improving the interface between solid and solid interfaces, and carefully analyzed the various unfavorable factors that affect the interface performance of the battery (Journal of Materials Chemistry A, , 4092; Chemistry of Materials, 2016, 28, 3578), summarizes the scientific issues and rules, draws the idea of ​​the battery solid electrolyte interface (SEI), creatively put forward "in situ self-formed solid electrolyte" solution, The formation of solid polymer electrolyte technology line, to build an integrated solid-state batteries, effectively reduce the interface impedance and enhance the battery performance. The method can be used to repair the solid interface of the solid-state battery and optimize the solid-solid interface performance. Based on this design concept, the Qingdao Energy Storage Research Group formed a low molecular weight VC (vinylene carbonate) solid polymer electrolyte by in-situ radical polymerization to form a high molecular weight PVC (poly (vinylene carbonate)) solid polymer electrolyte. 

It was found that this method can greatly reduce the interface impedance and broaden the electrochemical window effectively, which greatly improves the cycling stability and rate performance of the solid-state battery (Advanced Sciences, 2016, DOI: 10.1002 / advs .201600377). In addition, the polymer electrolyte was formed by in situ initiation polymerization of polytriethylene glycol divinyl ether by heating in the presence of initiator to form an integrated ion battery. The intimate contact between polymer electrolyte / electrode interface was successfully achieved and the interfacial impedance was reduced. Greatly improve the cycle stability of the battery (Small, 2016, DOI: 10.1002 / smll.201601530). "In-situ self-forming solid electrolyte" solution not only can effectively reduce the solid contact impedance; also can simplify the solid-state battery production steps, and the existing liquid lithium-ion battery production equipment and technology compatible with broad industrial promotion prospect.
In view of the rapid development of the electric vehicle market and the national "thirteen five" strategic planning of the macro layout, the urgent need to develop new ultra-high energy density lithium secondary battery. The R & D team focused on lithium-ion batteries to explore the construction of a "sandwich" lithium-polymer electrolyte designed to enhance the overall performance of lithium-ion batteries (Advanced Science, 2015, 2, 1500092; Advanced Energy Materials, 2016,6,1600751).

In the preparation of solid-state single-cell devices, the Qingdao Energy Storage Institute has adopted a polymer electrolyte design concept of "rigid and flexible" and "in situ self-forming mechanism", has developed a large capacity three-dimensional solid lithium battery. Solid-state battery does not fire and explosion, the safety performance is excellent, and the removal of the nail after the voltage has been restored, which once again highlights the solid electrolyte (solid electrolyte) Good self-repair performance and safety performance. In addition, the solid-state lithium battery high mechanical strength, 11,000 meters have been simulated deep-sea pressure chamber experiment, is now preparing to carry the deep-sea experiments. The related technology has applied for 29 Chinese invention patents and 3 international PCT patents.