Method for producing active material particles for lithium-ion rechargeable batteries, electrode, and lithium-ion rechargeable battery

Abstract

The purpose of the present invention is to produce active material particles for lithium-ion rechargeable batteries, the active material particles having good surface smoothness, improve cycle characteristics while minimizing the increase in internal resistance of the active material layer, and which minimize the breakdown of electrolyte, even at high potential. The active material particles for lithium-ion rechargeable batteries (X) is obtained by bringing into contact a composition containing a compound (a) having a metal element (M) selected from a group consisting of [Li, Mg, Ca, Sr, Ba, Pb, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, Cu, Zn, Al, In, Sn, Sb, Bi, La, Ce, Pr, Nd, Gd, Dy, Er and Yb] with a composition containing a fluoropolymer (b) having recurring units represented by -[CF2 - CR1R2]- (R1, R2 are H, F or -CF3), and heating.

Description

technical field [0001] The present invention relates to a method for producing active material particles for lithium ion secondary batteries, an electrode including the active material particles obtained by the production method, and a lithium ion secondary battery including the electrode. Background technique [0002] Lithium-ion secondary batteries are widely used in portable electronic devices such as mobile phones and notebook personal computers, and their application to automobiles is expected in recent years. LiCoO is used as a positive electrode active material for lithium-ion secondary batteries 2 , LiNiO 2 、LiNi 0.8 co 0.2 o 2 , LiMn 2 o 4 Composite oxides such as lithium and transition metals. Especially with LiCoO 2 Lithium-ion secondary batteries that use carbon such as lithium alloys, graphite, and carbon fibers as the negative electrode as the positive electrode active material are widely used as batteries with high energy density because they can obtai...

AI Technical Summary

Problems solved by technology

However, when the entire surface of the active material particle is covered with an inorganic material in this way, there is a problem that the intercalation and deintercalation of lithium ions becomes difficult, such as a decrease in the diffusion rate of lithium ions, and the internal resistance increases.

In addition, since the polymer material is acrylic, when it is used at a high potential where oxidation becomes high, problems such as decomposition of the electrolyte solution may occur.