Electrode binder composition, electrode slurry, electrode, and electrical storage device

#The present invention relates to an electrode binder composition, an electrode slurry that includes the binder composition and an electrode active material, an electrode that is produced by applying the slurry to a collector, and drying the slurry, and an electrical storage device that includes the electrode.

#In recent years, a high-voltage electrical storage device having a high energy density has been desired as a power supply for driving an electronic instrument. In particular, a lithium-ion battery or a lithium-ion capacitor is expected to be a high-voltage electrical storage device having a high energy density.

#An electrode used for such an electrical storage device is produced by applying a mixture of an electrode active material and polymer particles that function as a binder to the surface of a collector, and drying the mixture. The polymer particles are required to exhibit a capability of binding the electrode active material, a capability of binding the electrode active material and the collector, scratch resistance when winding the electrode, and powder fall resistance (i.e., a fine powder of the electrode active material or the like does not occur from an electrode composition layer (hereinafter may be referred to as “electrode active material layer”) due to cutting or the like). If the polymer particles satisfy these properties, it is possible to produce an electrical storage device that has high flexibility in structural design (e.g., an electrode folding method or an electrode winding radius), and can be reduced in size. It was found that a capability of binding the electrode active material, a capability of binding the electrode active material and the collector, and the powder fall resistance have an almost proportional relationship. Therefore, these properties may be comprehensively referred to as “adhesion”.

#FIG. 1 illustrates the DSC chart of the polymer particles obtained in Example 3.

#Exemplary embodiments of the invention are described in detail below. Note that the invention is not limited to the following exemplary embodiments. It is intended that the invention includes various modifications that may be practiced without departing from the scope of the invention. The term “(meth)acrylic acid” used herein refers to “acrylic acid” and “methacrylic acid”. The term “(meth)acrylate” used herein refers to “acrylate” and “methacrylate”.

#An electrode binder composition according to one embodiment of the invention is used to produce an electrode used for an electrical storage device, and includes (A) a polymer (hereinafter may be referred to as “polymer (A)”), (B) a compound represented by the following general formula (1) (hereinafter may be referred to as “compound (B)”), and (C) a liquid medium (hereinafter may be referred to as “liquid medium (C)”), the concentration of the compound (B) in the electrode binder composition being 5 to 500 ppm.

#wherein R1 and R2 independently represent a hydrogen atom, a halogen atom, or a monovalent alkyl group, and n is an integer from 0 to 5.