公开(公告)号：US06576369B1

公开(公告)日：2003-06-10

申请号：US09138561

申请日：1998-08-24

申请人： Koji Moriguchi ,  Mitsuharu Yonemura ,  Kazuhito Kamei ,  Noriyuki Negi ,  Masaru Abe ,  Hideya Kaminaka

发明人： Koji Moriguchi ,  Mitsuharu Yonemura ,  Kazuhito Kamei ,  Noriyuki Negi ,  Masaru Abe ,  Hideya Kaminaka

IPC分类号： C01B3104

CPC分类号： H01M4/583 ,  C01B32/20 ,  C01P2002/60 ,  C01P2006/12 ,  C01P2006/40 ,  H01M4/133 ,  H01M4/622 ,  H01M4/623 ,  H01M6/10 ,  H01M10/0525

摘要： A graphite powder has surface closed-end structures in which the graphite c-plane layers of the graphite layer crystal lattices have closed-ends on the surface of the graphite powder by linking the ends of one or more pairs of the c-plane layers, leaving interstices which are open on the surface of the graphite. The number of open interstices is at least 100 and at most 1500 per micrometer in a c-axis direction of the graphite. Preferably, the graphite powder has a specific surface area of 1.0 m2/g or less. Such a graphite powder can be prepared either by graphitizing a carbon material, which has been pulverized at a high speed under well-controlled conditions before and/or after the carbonization, or by subjecting a carbon material, which has been pulverized under well-controlled conditions before and/or after the carbonization, to graphitization and then to oxidative heat treatment at a temperature of 600-800° C. and finally to heat treatment at a temperature of 800° C. or higher in an inert gas. The graphite powder can be used to produce negative electrodes of lithium ion secondary batteries having a high discharge capacity of at least 320 mAh/g and a high charge/discharge coulombic efficiency of at least 90%.

摘要翻译： 石墨粉末具有表面封闭端结构，其中石墨层晶格的石墨c面层通过连接一对或多对c面层的端部而在石墨粉末的表面上具有封闭端， 留下在石墨表面开放的间隙。 在石墨的c轴方向上，开口间隙的数量为至少100个，最高为1500微米。 优选石墨粉的比表面积为1.0m 2 / g以下。 这样的石墨粉末可以通过在碳化之前和/或之后在良好控制的条件下高速粉碎的碳材料进行石墨化，或者通过将被粉碎的碳材料进行良好控制 在碳化之前和/或之后的条件进行石墨化，然后在600-800℃的温度下进行氧化热处理，最后在惰性气体中在800℃以上的温度下进行热处理。 该石墨粉末可用于制造具有至少320mAh / g的高放电容量和高充放电库仑效率至少为90％的锂离子二次电池的负极。