1. A battery pack comprising:
a protective circuit;
a charge control switch; and
a discharge control switch,
wherein the charge control switch and the discharge control switch are electrically connected to the protective circuit, and
wherein the charge control switch and the discharge control switch each comprise a transistor comprising an oxide semiconductor.
2. The battery pack according to claim 1, wherein the oxide semiconductor comprises at least one element selected from In, Ga, Sn, and Zn.
3. The battery pack according to claim 1, wherein each of the charge control switch and the discharge control switch further comprises a diode electrically connected to the transistor.
4. The battery pack according to claim 3, wherein the diode comprises an oxide semiconductor.
5. An electronic device comprising the battery pack according to claim 1.
6. A battery pack comprising:
a secondary battery;
a protective circuit;
a charge control switch; and
a discharge control switch,
wherein the charge control switch and the discharge control switch are electrically connected to the protective circuit,
wherein the charge control switch and the discharge control switch each comprise a transistor comprising an oxide semiconductor, and
wherein the protective circuit is configured to detect voltage of the secondary battery, compare the voltage with a predetermined voltage, and output a control signal in accordance with a comparison result, so that the charge control switch or the discharge control switch is turned on or turned off.
7. The battery pack according to claim 6, wherein the oxide semiconductor comprises at least one element selected from In, Ga, Sn, and Zn.
8. The battery pack according to claim 6, wherein each of the charge control switch and the discharge control switch further comprises a diode electrically connected to the transistor.
9. The battery pack according to claim 8, wherein the diode comprises an oxide semiconductor.
10. The battery pack according to claim 6, wherein the secondary battery, the charge control switch and the discharge control switch are connected in series.
11. The battery pack according to claim 6, wherein the secondary battery and the protective circuit are connected in parallel.
12. The battery pack according to claim 6, wherein the secondary battery is a lithium secondary battery.
13. An electronic device comprising the battery pack according to claim 6.
14. A battery pack comprising:
a protective circuit;
a charge control switch; and
a discharge control switch,
wherein the charge control switch and the discharge control switch each comprise a transistor comprising an oxide semiconductor, and
wherein the charge control switch and the discharge control switch are stacked over the protective circuit.
15. The battery pack according to claim 14, wherein the oxide semiconductor comprises at least one element selected from In, Ga, Sn, and Zn.
16. The battery pack according to claim 14, wherein each of the charge control switch and the discharge control switch further comprises a diode electrically connected to the transistor.
17. The battery pack according to claim 16, wherein the diode comprises an oxide semiconductor.
18. An electronic device comprising the battery pack according to claim 14.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A process of production of a compressor shoe including a process of quenching a material in a quenching furnace comprised of chrome andor manganese steel and forming a shoe shape,
said quenching process comprising a step of preventing oxidation of the chrome andor manganese, wherein said step is lowering a pressure in the quenching furnace to create a vacuum.
2. A process of production of a compressor shoe including a process of quenching a material in a quenching furnace comprised of chrome andor manganese steel and forming a shoe shape,
said quenching process comprising a step of preventing oxidation of the chrome andor manganese, wherein said step is replacing an atmosphere of the quenching furnace by an inert gas or modified gas.
3. A process of production of a compressor shoe including a process of quenching a material in a quenching furnace comprised of chrome andor manganese steel and forming a shoe shape,
said quenching process comprising a step of preventing oxidation of the chrome andor manganese, wherein said step is forming an anti-oxidation film able to prevent oxidation of the chrome andor manganese on the surface of the material before quenching, and wherein said anti-oxidation film is a phosphate film.