GRAPHITE PARTICLE FOR LITHIUM ION SECONDARY BATTERY NEGATIVE ELECTRODE MATERIAL, LITHIUM ION SECONDARY BATTERY NEGATIVE ELECTRODE AND LITHIUM ION SECONDARY BATTERY

摘要

PROBLEM TO BE SOLVED: To provide: a negative electrode material superior in at least one of initial charge/discharge efficiency, rapid chargeability, rapid dischargeability and long-term cycle characteristic; a negative electrode arranged by use of such a negative electrode material; and a lithium secondary battery.SOLUTION: A group of graphite particles for lithium ion secondary battery negative electrode material comprises a mixture of: composite graphite particles (C1) each having a sphere- or generally sphere-shaped spheroidized graphite particle (A) and a carbonaceous material (B1) present in the spheroidized graphite particle and/or on at least part of the surface thereof; and composite graphite particles (C2) each having a sphere- or generally sphere-shaped spheroidized graphite particle (A) and a graphite material (B2) present in the spheroidized graphite particle and/or on at least part of the surface thereof. The mixture satisfies the requirements (1) to (5) described below. (1) The lattice spacing (d) of a carbon net-plane layer is 0.3360 nm or less; (2) the tap density is 1.0 g/cmor more; (3) the average particle diameter is 5-25 μm; (4) the average aspect ratio is 1.2 to less than 4.0; and (5) the size of pores of 0.5 μm or smaller in pore volume is 0.08 ml/g or less according to a mercury porosimeter.SELECTED DRAWING: None