Nonaqueous electrolyte secondary battery with rolled electrode assembly
View Patent ↗The nonaqueous electrolyte secondary battery includes a rolled electrode assembly 14 E formed by rolling a positive electrode plate 11 and a negative electrode plate 12 with a separator 13 interposed therebetween, the separator 13 is fixed on the outermost periphery of the rolled electrode assembly 14 E with an adhesive tape for fixing a roll end 30 e , an exposed portion of a negative electrode substrate 12 c without an active material mixture layer 12 b is placed on an outermost periphery side of the negative electrode plate 12 , a negative electrode tab 12 a is connected to the negative electrode substrate 12 c on an outermost periphery side, and the adhesive tape 30 e is not overlapped with a roll end 11 d of the positive electrode plate 11 and a roll end 12 d of the negative electrode substrate 12 c . Thus the battery is seldom broken even when charging and discharging are repeatedly provided at high voltage.
1. A nonaqueous electrolyte secondary battery comprising:
a cylindrical shaped battery outer can; and
a rolled electrode assembly formed by rolling a positive electrode plate and a negative electrode plate with a separator interposed therebetween to insulate each other,
the positive electrode plate including a positive electrode substrate in which both sides of the positive electrode substrate is coated with a positive electrode active material mixture,
the negative electrode plate including a negative electrode substrate in which both sides of the negative electrode substrate is coated with a negative electrode active material mixture,
the rolled electrode assembly being put into the battery outer can, the separator being placed on an outermost periphery of the rolled electrode assembly,
the separator being fixed on the outermost periphery of the rolled electrode assembly with an adhesive tape for fixing a roll end,
an exposed portion of the negative electrode substrate without a negative electrode active material mixture layer being placed on an outermost periphery side of the negative electrode plate, a negative electrode tab being connected to the negative electrode substrate on the outermost periphery side, and
the adhesive tape for fixing a roll end of the separator does not extend beyond and cover the roll end point of the positive electrode substrate and a roll end point of the negative electrode substrate.
2. The nonaqueous electrolyte secondary battery according to claim 1 , wherein the negative electrode substrate is made of copper foil, and a thickness of the negative electrode substrate is 10 μm or less and 6 μm or more.
3. The nonaqueous electrolyte secondary battery according to claim 1 , wherein the positive electrode plate has a final charge voltage of 4.4 V or higher vs. Li.
4. The nonaqueous electrolyte secondary battery according to claim 2 , wherein the positive electrode plate has a final charge voltage of 4.4 V or higher vs. Li.
5. The nonaqueous electrolyte secondary battery according to claim 1 , wherein the negative electrode substrate includes an outermost roll being placed inside the separator which is placed on the outermost periphery of the rolled electrode assembly.