Production method for non-aqueous electrolyte secondary battery active material providing lithium insertion and solution contact
摘要
說明書
In the production method of the negative electrode active material of the present invention, the silicon compound in which Li has been inserted is contacted with the solution B to desorb a part of active Li from the silicon compound to prevent a violent reaction (a reaction accompanying ignition or boiling of the solvent) from occurring in making contact with the solution C. Thus, the silicon compound does not cause the violent reaction and the battery characteristics may be suppressed from deteriorating due to heat generation during preparation of the electrode.
At this time, in the step of making the silicon compound contact with the solution B, it is preferable to make the silicon compound contact with the solution B for 3 minutes or longer.
When the silicon compound is contacted with the solution B for 3 minutes or longer, the active Li may be more sufficiently desorbed.
Further, at this time, it is preferable that, in the step of inserting lithium, the silicon compound is contacted with a solution A (here, the solution A has the ether-based solvent as the solvent) containing lithium for 3 minutes or longer to insert the lithium into the silicon compound.
Thus, the Li may be inserted without largely increasing the temperature. Thereby, in the silicon compound, since a crystalline Li silicate that causes deterioration of the cycle characteristics is difficult to occur, the cycle characteristics may be prevented from deteriorating. Further, by contacting with the solution A for 3 minutes or longer, the Li may be more sufficiently inserted into the silicon compound.
