Lithium ion polymer secondary cell
A porous element containing a fluoropolymer comprising vinylidene fluoride as a main unit and having a density of 0.55–1.30 g/cm 3 and a Gurley value of not more than 150 sec/100 cc is used as a polymer substrate of a solid electrolyte to be placed between a positive electrode and a negative electrode. As a result, the solid electrolyte layer shows fine ion conductivity and an ion polymer secondary battery having strikingly improved low temperature characteristics, cycle characteristics and high-rate discharge characteristics as compared to conventional batteries can be obtained.
1. A lithium ion polymer secondary battery comprising a positive electrode, a negative electrode and a solid electrolyte layer comprising a porous element comprising a fluoropolymer comprising vinylidene fluoride as a main unit and having a density of 0.55–1.30 g/cm 3 and a Gurley value of 35–50 sec/100 cc, a salt and a compatible solvent comprising a mixture of ethylene carbonate, propylene carbonate, ethylmethyl carbonate, and diethyl carbonate, which is disposed between the positive electrode and the negative electrode.
2. The lithium ion polymer secondary battery of claim 1 , wherein the salt is at least one kind of compound selected from LiClO 4 , LiBF 4 , LiPF 6 , LiAsF 6 , LiCF 3 SO 3 , LiAlCl 4 and Li(CF 3 SO 2 ) 2 N.
3. The lithium ion polymer secondary battery of claim 1 , wherein the positive electrode active material is a Li-transition metal composite oxide.
4. The lithium ion polymer secondary battery of claim 2 , wherein the positive electrode active material is a Li-transition metal composite oxide.
5. The lithium ion polymer secondary battery of claim 1 , wherein the negative electrode active material is a graphite.
6. The lithium ion polymer secondary battery of claim 2 , wherein the negative electrode active material is a graphite.
7. The lithium ion polymer secondary battery of claim 3 , wherein the negative electrode active material is a graphite.
8. The lithium ion polymer secondary battery of claim 4 , wherein the negative electrode active material is a graphite.
9. The lithium ion polymer secondary battery of claim 1 , wherein
the positive electrode is a belt-shaped positive electrode comprising positive electrode active material layers, which comprise an active material and a conductive material, formed on both surfaces of a belt-shaped collector,
the negative electrode is a belt-shaped negative electrode comprising negative electrode active material layers formed on both surfaces of a belt-shaped collector, and
these belt-shaped positive electrode and belt-shaped negative electrode and the solid electrolyte layer having a belt shape and being interposed between said electrodes are spirally wound to constitute a roll, wherein
the total thickness A of the positive electrode active material layers formed on both surfaces of the belt-shaped collector of said belt-shaped positive electrode and the total thickness B of the negative electrode active material layers formed on both surfaces of the belt-shaped collector of said belt-shaped negative electrode are each 80 μm–250 μm,and
the ratio (A/B) of the total thickness A to the total thickness B is 0.4–2.2.
10. The lithium ion polymer secondary battery of claim 2 , wherein
the positive electrode is a belt-shaped positive electrode comprising positive electrode active material layers, which comprise an active material and a conductive material, formed on both surfaces of a belt-shaped collector,
the negative electrode is a belt-shaped negative electrode comprising negative electrode active material layers formed on both surfaces of a belt-shaped collector, and
these belt-shaped positive electrode and belt-shaped negative electrode and the solid electrolyte layer having a belt shape and being interposed between said electrodes are spirally wound to constitute a roll, wherein
the total thickness A of the positive electrode active material layers formed on both surfaces of the belt-shaped collector of said belt-shaped positive electrode and the total thickness B of the negative electrode active material layers formed on both surfaces of the belt-shaped collector of said belt-shaped negative electrode are each 80 μm–250 μm, and
the ratio (A/B) of the total thickness A to the total thickness B is 0.4–2.2.
11. The lithium ion polymer secondary battery of claim 3 , wherein
the positive electrode is a belt-shaped positive electrode comprising positive electrode active material layers, which comprise an active material and a conductive material, formed on both surfaces of a belt-shaped collector,
the negative electrode is a belt-shaped negative electrode comprising negative electrode active material layers formed on both surfaces of a belt-shaped collector, and
these belt-shaped positive electrode and belt-shaped negative electrode and the solid electrolyte layer having a belt shape and being interposed between said electrodes are spirally wound to constitute a roll, wherein
the total thickness A of the positive electrode active material layers formed on both surfaces of the belt-shaped collector of said belt-shaped positive electrode and the total thickness B of the negative electrode active material layers formed on both surfaces of the belt-shaped collector of said belt-shaped negative electrode are each 80 μm–250 μm,and
the ratio (A/B) of the total thickness A to the total thickness B is 0.4–2.2.
12. The lithium ion polymer secondary battery of claim 4 , wherein
the positive electrode is a belt-shaped positive electrode comprising positive electrode active material layers, which comprise an active material and a conductive material, formed on both surfaces of a belt-shaped collector,
the negative electrode is a belt-shaped negative electrode comprising negative electrode active material layers formed on both surfaces of a belt-shaped collector, and
these belt-shaped positive electrode and belt-shaped negative electrode and the solid electrolyte layer having a belt shape and being interposed between said electrodes are spirally wound to constitute a roll, wherein
the total thickness A of the positive electrode active material layers formed on both surfaces of the belt-shaped collector of said belt-shaped positive electrode and the total thickness B of the negative electrode active material layers formed on both surfaces of the belt-shaped collector of said belt-shaped negative electrode are each 80 μm–250 μm, and
the ratio (A/B) of the total thickness A to the total thickness B is 0.4–2.2.
13. The lithium ion polymer secondary battery of claim 5 , wherein
the positive electrode is a belt-shaped positive electrode comprising positive electrode active material layers, which comprise an active material and a conductive material, formed on both surfaces of a belt-shaped collector,
the negative electrode is a belt-shaped negative electrode comprising negative electrode active material layers formed on both surfaces of a belt-shaped collector, and
these belt-shaped positive electrode and belt-shaped negative electrode and the solid electrolyte layer having a belt shape and being interposed between said electrodes are spirally wound to constitute a roll, wherein
the total thickness A of the positive electrode active material layers formed on both surfaces of the belt-shaped collector of said belt-shaped positive electrode and the total thickness B of the negative electrode active material layers formed on both surfaces of the belt-shaped collector of said belt-shaped negative electrode are each 80 μm–250 μm, and
the ratio (A/B) of the total thickness A to the total thickness B is 0.4–2.2.
14. The lithium ion polymer secondary battery of claim 6 , wherein
the positive electrode is a belt-shaped positive electrode comprising positive electrode active material layers, which comprise an active material and a conductive material, formed on both surfaces of a belt-shaped collector,
the negative electrode is a belt-shaped negative electrode comprising negative electrode active material layers formed on both surfaces of a belt-shaped collector, and
these belt-shaped positive electrode and belt-shaped negative electrode and the solid electrolyte layer having a belt shape and being interposed between said electrodes are spirally wound to constitute a roll, wherein
the total thickness A of the positive electrode active material layers formed on both surfaces of the belt-shaped collector of said belt-shaped positive electrode and the total thickness B of the negative electrode active material layers formed on both surfaces of the belt-shaped collector of said belt-shaped negative electrode are each 80 μm–250 μm, and
the ratio (A/B) of the total thickness A to the total thickness B is 0.4–2.2.
15. The lithium ion polymer secondary battery of claim 7 , wherein
the positive electrode is a belt-shaped positive electrode comprising positive electrode active material layers, which comprise an active material and a conductive material, formed on both surfaces of a belt-shaped collector,
the negative electrode is a belt-shaped negative electrode comprising negative electrode active material layers formed on both surfaces of a belt-shaped collector, and
these belt-shaped positive electrode and belt-shaped negative electrode and the solid electrolyte layer having a belt shape and being interposed between said electrodes are spirally wound to constitute a roll, wherein
the total thickness A of the positive electrode active material layers formed on both surfaces of the belt-shaped collector of said belt-shaped positive electrode and the total thickness B of the negative electrode active material layers formed on both surfaces of the belt-shaped collector of said belt-shaped negative electrode are each 80 μm–250 μm,and
the ratio (A/B) of the total thickness A to the total thickness B is 0.4–2.2.
16. The lithium ion polymer secondary battery of claim 8 , wherein
the positive electrode is a belt-shaped positive electrode comprising positive electrode active material layers, which comprise an active material and a conductive material, formed on both surfaces of a belt-shaped collector,
the negative electrode is a belt-shaped negative electrode comprising negative electrode active material layers formed on both surfaces of a belt-shaped collector, and
these belt-shaped positive electrode and belt-shaped negative electrode and the solid electrolyte layer having a belt shape and being interposed between said electrodes are spirally wound to constitute a roll, wherein
the total thickness A of the positive electrode active material layers formed on both surfaces of the belt-shaped collector of said belt-shaped positive electrode and the total thickness B of the negative electrode active material layers formed on both surfaces of the belt-shaped collector of said belt-shaped negative electrode are each 80 μm–250 μm,and
the ratio (A/B) of the total thickness A to the total thickness B is 0.4–2.2.
17. The lithium ion polymer secondary battery of claim 1 , wherein
the positive electrode is a belt-shaped positive electrode comprising positive electrode active material layers, which comprise an active material and a conductive material, formed on both surfaces of a belt-shaped collector,
the negative electrode is a belt-shaped negative electrode comprising negative electrode active material layers formed on both surfaces of a belt-shaped collector, and
these belt-shaped positive electrode and belt-shaped negative electrode and the solid electrolyte layer having a belt shape and being interposed between the electrodes are spirally wound to constitute a roll, wherein
an outermost roll part of said belt-shaped negative electrode is disposed on a still outer periphery of the outermost roll part of said belt-shaped positive electrode, and a first extrusion part extruding from a free end of the outermost roll part of said belt-shaped positive electrode is formed on a free end of the outermost roll part of said belt-shaped negative electrode,
an innermost roll part of said belt-shaped negative electrode is disposed on a still inner periphery of the innermost roll part of said belt-shaped positive electrode and a second extrusion part extruding from a free end of the innermost roll part of said belt-shaped positive electrode is formed on a free end of the innermost roll part of said belt-shaped negative electrode, and
a third and a fourth extrusion parts extruding from both ends in the width direction of said belt-shaped positive electrode are respectively formed on both ends in the width direction of said belt-shaped negative electrode.
18. The lithium ion polymer secondary battery of claim 2 , wherein
the positive electrode is a belt-shaped positive electrode comprising positive electrode active material layers, which comprise an active material and a conductive material, formed on both surfaces of a belt-shaped collector,
the negative electrode is a belt-shaped negative electrode comprising negative electrode active material layers formed on both surfaces of a belt-shaped collector, and
these belt-shaped positive electrode and belt-shaped negative electrode and the solid electrolyte layer having a belt shape and being interposed between the electrodes are spirally wound to constitute a roll, wherein
an outermost roll part of said belt-shaped negative electrode is disposed on a still outer periphery of the outermost roll part of said belt-shaped positive electrode, and a first extrusion part extruding from a free end of the outermost roll part of said belt-shaped positive electrode is formed on a free end of the outermost roll part of said belt-shaped negative electrode,
an innermost roll part of said belt-shaped negative electrode is disposed on a still inner periphery of the innermost roll part of said belt-shaped positive electrode and a second extrusion part extruding from a free end of the innermost roll part of said belt-shaped positive electrode is formed on a free end of the innermost roll part of said belt-shaped negative electrode, and
a third and a fourth extrusion parts extruding from both ends in the width direction of said belt-shaped positive electrode are respectively formed on both ends in the width direction of said belt-shaped negative electrode.
19. The lithium ion polymer secondary battery of claim 3 , wherein
the positive electrode is a belt-shaped positive electrode comprising positive electrode active material layers, which comprise an active material and a conductive material, formed on both surfaces of a belt-shaped collector,
the negative electrode is a belt-shaped negative electrode comprising negative electrode active material layers formed on both surfaces of a belt-shaped collector, and
these belt-shaped positive electrode and belt-shaped negative electrode and the solid electrolyte layer having a belt shape and being interposed between the electrodes are spirally wound to constitute a roll, wherein
an outermost roll part of said belt-shaped negative electrode is disposed on a still outer periphery of the outermost roll part of said belt-shaped positive electrode, and a first extrusion part extruding from a free end of the outermost roll part of said belt-shaped positive electrode is formed on a free end of the outermost roll part of said belt-shaped negative electrode,
an innermost roll part of said belt-shaped negative electrode is disposed on a still inner periphery of the innermost roll part of said belt-shaped positive electrode and a second extrusion part extruding from a free end of the innermost roll part of said belt-shaped positive electrode is formed on a free end of the innermost roll part of said belt-shaped negative electrode, and
a third and a fourth extrusion parts extruding from both ends in the width direction of said belt-shaped positive electrode are respectively formed on both ends in the width direction of said belt-shaped negative electrode.
20. The lithium ion polymer secondary battery of claim 4 , wherein
the positive electrode is a belt-shaped positive electrode comprising positive electrode active material layers, which comprise an active material and a conductive material, formed on both surfaces of a belt-shaped collector,
the negative electrode is a belt-shaped negative electrode comprising negative electrode active material layers formed on both surfaces of a belt-shaped collector, and
these belt-shaped positive electrode and belt-shaped negative electrode and the solid electrolyte layer having a belt shape and being interposed between the electrodes are spirally wound to constitute a roll, wherein
an outermost roll part of said belt-shaped negative electrode is disposed on a still outer periphery of the outermost roll part of said belt-shaped positive electrode, and a first extrusion part extruding from a free end of the outermost roll part of said belt-shaped positive electrode is formed on a free end of the outermost roll part of said belt-shaped negative electrode,
an innermost roll part of said belt-shaped negative electrode is disposed on a still inner periphery of the innermost roll part of said belt-shaped positive electrode and a second extrusion part extruding from a free end of the innermost roll part of said belt-shaped positive electrode is formed on a free end of the innermost roll part of said belt-shaped negative electrode, and
a third and a fourth extrusion parts extruding from both ends in the width direction of said belt-shaped positive electrode are respectively formed on both ends in the width direction of said belt-shaped negative electrode.
21. The lithium ion polymer secondary battery of claim 5 , wherein
the positive electrode is a belt-shaped positive electrode comprising positive electrode active material layers, which comprise an active material and a conductive material, formed on both surfaces of a belt-shaped collector,
the negative electrode is a belt-shaped negative electrode comprising negative electrode active material layers formed on both surfaces of a belt-shaped collector, and
these belt-shaped positive electrode and belt-shaped negative electrode and the solid electrolyte layer having a belt shape and being interposed between the electrodes are spirally wound to constitute a roll, wherein
an outermost roll part of said belt-shaped negative electrode is disposed on a still outer periphery of the outermost roll part of said belt-shaped positive electrode, and a first extrusion part extruding from a free end of the outermost roll part of said belt-shaped positive electrode is formed on a free end of the outermost roll part of said belt-shaped negative electrode,
an innermost roll part of said belt-shaped negative electrode is disposed on a still inner periphery of the innermost roll part of said belt-shaped positive electrode and a second extrusion part extruding from a free end of the innermost roll part of said belt-shaped positive electrode is formed on a free end of the innermost roll part of said belt-shaped negative electrode, and
a third and a fourth extrusion parts extruding from both ends in the width direction of said belt-shaped positive electrode are respectively formed on both ends in the width direction of said belt-shaped negative electrode.
22. The lithium ion polymer secondary battery of claim 6 , wherein
the positive electrode is a belt-shaped positive electrode comprising positive electrode active material layers, which comprise an active material and a conductive material, formed on both surfaces of a belt-shaped collector,
the negative electrode is a belt-shaped negative electrode comprising negative electrode active material layers formed on both surfaces of a belt-shaped collector, and
these belt-shaped positive electrode and belt-shaped negative electrode and the solid electrolyte layer having a belt shape and being interposed between the electrodes are spirally wound to constitute a roll, wherein
an outermost roll part of said belt-shaped negative electrode is disposed on a still outer periphery of the outermost roll part of said belt-shaped positive electrode, and a first extrusion part extruding from a free end of the outermost roll part of said belt-shaped positive electrode is formed on a free end of the outermost roll part of said belt-shaped negative electrode,
an innermost roll part of said belt-shaped negative electrode is disposed on a still inner periphery of the innermost roll part of said belt-shaped positive electrode and a second extrusion part extruding from a free end of the innermost roll part of said belt-shaped positive electrode is formed on a free end of the innermost roll part of said belt-shaped negative electrode, and
a third and a fourth extrusion parts extruding from both ends in the width direction of said belt-shaped positive electrode are respectively formed on both ends in the width direction of said belt-shaped negative electrode.
23. The lithium ion polymer secondary battery of claim 7 , wherein
the positive electrode is a belt-shaped positive electrode comprising positive electrode active material layers, which comprise an active material and a conductive material, formed on both surfaces of a belt-shaped collector,
the negative electrode is a belt-shaped negative electrode comprising negative electrode active material layers formed on both surfaces of a belt-shaped collector, and
these belt-shaped positive electrode and belt-shaped negative electrode and the solid electrolyte layer having a belt shape and being interposed between the electrodes are spirally wound to constitute a roll, wherein
an outermost roll part of said belt-shaped negative electrode is disposed on a still outer periphery of the outermost roll part of said belt-shaped positive electrode, and a first extrusion part extruding from a free end of the outermost roll part of said belt-shaped positive electrode is formed on a free end of the outermost roll part of said belt-shaped negative electrode,
an innermost roll part of said belt-shaped negative electrode is disposed on a still inner periphery of the innermost roll part of said belt-shaped positive electrode and a second extrusion part extruding from a free end of the innermost roll part of said belt-shaped positive electrode is formed on a free end of the innermost roll part of said belt-shaped negative electrode, and
a third and a fourth extrusion parts extruding from both ends in the width direction of said belt-shaped positive electrode are respectively formed on both ends in the width direction of said belt-shaped negative electrode.
24. The lithium ion polymer secondary battery of claim 8 , wherein
the positive electrode is a belt-shaped positive electrode comprising positive electrode active material layers, which comprise an active material and a conductive material, formed on both surfaces of a belt-shaped collector,
the negative electrode is a belt-shaped negative electrode comprising negative electrode active material layers formed on both surfaces of a belt-shaped collector, and
these belt-shaped positive electrode and belt-shaped negative electrode and the solid electrolyte layer having a belt shape and being interposed between the electrodes are spirally wound to constitute a roll, wherein
an outermost roll part of said belt-shaped negative electrode is disposed on a still outer periphery of the outermost roll part of said belt-shaped positive electrode, and a first extrusion part extruding from a free end of the outermost roll part of said belt-shaped positive electrode is formed on a free end of the outermost roll part of said belt-shaped negative electrode,
an innermost roll part of said belt-shaped negative electrode is disposed on a still inner periphery of the innermost roll part of said belt-shaped positive electrode and a second extrusion part extruding from a free end of the innermost roll part of said belt-shaped positive electrode is formed on a free end of the innermost roll part of said belt-shaped negative electrode, and
a third and a fourth extrusion parts extruding from both ends in the width direction of said belt-shaped positive electrode are respectively formed on both ends in the width direction of said belt-shaped negative electrode.