Battery apparatus

Claim 2

A battery apparatus comprising: (1) a switching device connected between a battery charger and a rechargeable battery; (2) a pulse control circuit to control on and off the switching device, the pulse control circuit turn off the switching device and suspend charging when rechargeable battery voltage exceeds a specified voltage, and turn on the switching device and resume charging when rechargeable battery voltage drops below the specified voltage; and (3) an over-ride circuit to detect a cut-off of charging voltage application to the rechargeable battery and to force the switching device on.

Claim 3

A battery apparatus as recited in claim 1 wherein the rechargeable battery is a lithium ion rechargeable battery.

Claim 4

A battery apparatus as recited in claim 1 wherein the battery apparatus contains a rechargeable battery protection circuit.

Claim 5

A battery apparatus as recited in claim 3 wherein the switching device is an FET contained in the rechargeable battery protection circuit.

Claim 6

A battery apparatus as recited in claim 3 wherein the pulse control circuit is a voltage detection circuit and is contained in the rechargeable battery protection circuit.

Claim 7

A battery apparatus as recited in claim 5 wherein the voltage detection circuit is a circuit which, when battery voltage exceeds the specified voltage, turns the switching device off after a fixed period of time.

Claim 8

A battery apparatus as recited in claim 3 wherein the over-ride circuit is contained in a rechargeable battery protection circuit.

Claim 9

A battery apparatus comprising: (a) a battery charger to charge a rechargeable battery; and (b) a battery pack which attaches to the battery charger in a detachable manner including: (1) a switching device connected between the battery charger and the rechargeable battery; (2) a pulse control circuit to control on and off the switching device, the pulse control circuit turn off the switching device and suspend charging when rechargeable battery voltage exceeds a specified voltage, and turn on the switching device and resume charging when rechargeable battery voltage drops below the specified voltage; and (3) an over-ride circuit to detect a cut-off of charging voltage application to the rechargeable battery and to force the switching device on.

Claim 10

A battery apparatus comprising: (a) a battery charger to charge a rechargeable battery; and (b) a battery pack which attaches to the battery charger in a detachable manner including: (1) a switching device connected between the battery charger and the rechargeable battery; (2) a pulse control circuit to control on and off the switching device, the pulse control circuit turn off the switching device and suspend charging when rechargeable battery voltage exceeds a specified voltage, and turn on the switching device and resume charging when rechargeable battery voltage drops below the specified voltage; and (3) an over-ride circuit to detect a cut-off of charging voltage application to the rechargeable battery and to force the switching device on.

Claim 11

A battery apparatus as recited in claim 8 wherein the battery pack contains a protection circuit, and the protection circuit contains the switching device, the pulse control circuit, and the over-ride circuit.

Claim 12

A battery apparatus as recited in claim 8 wherein the rechargeable battery is a lithium ion rechargeable battery.

Claim 13

A battery apparatus as recited in claim 9 wherein the switching device is an FET.

Claim 14

A battery apparatus as recited in claim 9 wherein the pulse control circuit is a voltage detection circuit.

Claim 15

A battery apparatus as recited in claim 12 wherein the voltage detection circuit is a circuit which, when battery voltage exceeds the specified voltage, turns the switching device off after a fixed period of time.

Claim 16

A battery apparatus as recited in claim 9 wherein the over-ride circuit is a circuit to detect removal of the battery pack from the battery charger and to turn the switching device on.

Claim 17

A battery apparatus comprising: (1) a switching device; (2) a pulse control circuit to control on and off the switching device, the pulse control circuit turn off the switching device and suspend charging when rechargeable battery voltage exceeds a specified voltage, and turn on the switching device and resume charging when rechargeable battery voltage drops below the specified voltage; and (3) a forced discharge circuit to forcibly discharge the rechargeable battery until battery voltage drops below the specified voltage, when it detects a cut-off of charging voltage application to the rechargeable battery.

Claim 18

A battery apparatus comprising: (1) a switching device; (2) a pulse control circuit to control on and off the switching device, the pulse control circuit turn off the switching device and suspend charging when rechargeable battery voltage exceeds a specified voltage, and turn on the switching device and resume charging when rechargeable battery voltage drops below the specified voltage; and (3) a forced discharge circuit to forcibly discharge the rechargeable battery until battery voltage drops below the specified voltage, when it detects a cut-off of charging voltage application to the rechargeable battery.

Claim 19

A battery apparatus as recited in claim 15 wherein the rechargeable battery is a lithium ion rechargeable battery.

Claim 20

A battery apparatus as recited in claim 15 wherein the battery apparatus contains a rechargeable battery protection circuit.

Claim 21

A battery apparatus as recited in claim 17 wherein the switching device is an FET contained in the rechargeable battery protection circuit.

Claim 22

A battery apparatus as recited in claim 17 wherein the pulse control circuit is a voltage detection circuit and is contained in the rechargeable battery protection circuit.

Claim 23

A battery apparatus as recited in claim 19 wherein the voltage detection circuit is a circuit which, when battery voltage exceeds the specified voltage, turns the switching device off after a fixed period of time.

Claim 24

A battery apparatus as recited in claim 15 wherein the forced discharge circuit is contained in a rechargeable battery protection circuit.

Claim 25

A battery apparatus comprising: (a) a battery charger to charge a rechargeable battery; and (b) a battery pack which attaches to the battery charger in a detachable manner including: (1) a switching device connected between the battery charger and the rechargeable battery; (2) a pulse control circuit to control on and off the switching device, the pulse control circuit turn off the switching device and suspend charging when rechargeable battery voltage exceeds a specified voltage, and turn on the switching device and resume charging when rechargeable battery voltage drops below the specified voltage; and (3) a forced discharge circuit to forcibly discharge the rechargeable battery until battery voltage drops below the specified voltage, when it detects cut-off of charging voltage application to the rechargeable battery.

Claim 26

A battery apparatus comprising: (a) a battery charger to charge a rechargeable battery; and (b) a battery pack which attaches to the battery charger in a detachable manner including: (1) a switching device connected between the battery charger and the rechargeable battery; (2) a pulse control circuit to control on and off the switching device, the pulse control circuit turn off the switching device and suspend charging when rechargeable battery voltage exceeds a specified voltage, and turn on the switching device and resume charging when rechargeable battery voltage drops below the specified voltage; and (3) a forced discharge circuit to forcibly discharge the rechargeable battery until battery voltage drops below the specified voltage, when it detects cut-off of charging voltage application to the rechargeable battery.

Claim 27

A battery apparatus as recited in claim 22 wherein the battery pack contains a protection circuit, and the protection circuit contains the switching device, the pulse control circuit, and the forced discharge circuit.

Claim 28

A battery apparatus as recited in claim 22 wherein the rechargeable battery is a lithium ion rechargeable battery.

Claim 29

A battery apparatus as recited in claim 22 wherein the switching device is an FET.

Claim 30

A battery apparatus as recited in claim 23 wherein the pulse control circuit is a voltage detection circuit.

Claim 31

A battery apparatus as recited in claim 22 wherein the voltage detection circuit is a circuit which, when battery voltage exceeds the specified voltage, turns the switching device off after a fixed period of time.

Claim 32

A battery apparatus as recited in claim 22 wherein the forced discharge circuit detects removal of the battery pack from the battery charger and forcibly discharges the rechargeable battery until battery voltage drops below the specified voltage.