Secondary battery electrode, and method for producing same
摘要
說明書
As an example, when the negative electrode active material is a material which is difficult to be plastically deformed, such as hard carbon or soft carbon, or though the negative electrode active material is a material capable of plastic deformation if necessary, such as natural graphite, a raw material including the particulate electrode active material (hard carbon, soft carbon, natural graphite, and the like) and a carbon precursor is molded to produce a molded body, and then heat is applied thereto to convert the carbon precursor into carbon, thereby producing the active material bulk in the form of a sintered body. In this case, the sintered body may be in the state in which the particulate electrode active materials are at least bound carbon converted from the carbon precursor (pyrocarbon).
That is, the active material bulk may include a particulate active material and pyrocarbon which binds the particulate active material, and the active material film produced from the active material bulk may also include the particulate active material and the pyrocarbon binding the electrode active material particles.
In the conventional slurry-based electrode production technique, the slurry of particles should be applied on a current collector to maintain a layer structure of active material “mixed layer”, and thus, the electrode active material fraction in the active material layer is inhibited and the electrical properties are decreased, but the use of the binder was inevitable.
However, in the production method according to an exemplary embodiment of the present invention, a sintered body capable of free-standing may be produced by interparticle grain boundary or neck formation of the electrode active material, binding by carbon converted from a carbon precursor (pyrocarbon), or the like.
