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A method and apparatus for charging a rechargeable battery comprises determining a safe charging voltage Vsafe that is the maximum open circuit voltage of the battery which provides a minimum battery capacity for a predetermined number of charge and discharge cycles of the battery. The battery is ch

A method and apparatus for charging a rechargeable battery comprises determining a safe charging voltage Vsafe that is the maximum open circuit voltage of the battery which provides a minimum battery capacity for a predetermined number of charge and discharge cycles of the battery. The battery is charged with a voltage Vhv which is higher than the Vsafe. The charging voltage is removed and open circuit voltage of the battery is measured. The charging and measuring steps are repeated when the open circuit voltage is less than Vsafe, and the charging process is terminated when the open circuit voltage is substantially equal to Vsafe.

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1. A method of charging a, the method comprising: (a) determining a safe charging voltage Vsafe that is the maximum open circuit voltage of the battery which provides a minimum battery capacity for a predetermined number of charge and discharge cycles of the battery;(b) charging the battery with a c

1. A method of charging a, the method comprising: (a) determining a safe charging voltage Vsafe that is the maximum open circuit voltage of the battery which provides a minimum battery capacity for a predetermined number of charge and discharge cycles of the battery;(b) charging the battery with a charging voltage Vhv which is higher than the Vsafe;(c) removing the charging voltage Vhv and measuring the open circuit voltage of the battery; and(d) repeating steps (b) and (c) when the open circuit voltage is less than Vsafe or terminating charging when the open circuit voltage is substantially equal to or greater than Vsafe. 2. A method according to claim 1 comprising providing a battery that includes a cathode comprising LiCoO2, and determining a safe charging voltage Vsafe that is from about 4.1 to about 4.2 volts. 3. A method according to claim 1 comprising providing a battery that includes a cathode comprising LiCoO2, and determining a safe charging voltage Vsafe that provides a minimum battery 5-hour rate discharge capacity of at least about 70% of the initial capacity after at least about 1000 charge and 80%-depth discharge cycles of the battery. 4. A method according to claim 1 comprising providing a battery that includes a cathode comprising LiCoO2, and determining a safe charging voltage Vsafe that provides a minimum battery 5-hour rate discharge capacity of at least about 70% of the initial capacity after at least about 3000 charge and 80%-depth discharge cycles of the battery. 5. A method according to claim 1 wherein the battery comprises an anode current collector and a cathode current collector, and wherein (b) comprises connecting a positive polarity of a direct current (DC) power source to the cathode current collector of the battery and connecting a negative polarity of the DC power source to the anode current collector of a rechargeable battery. 6. A method according to claim 1 comprising charging the battery with a voltage Vhv which is higher than the Vsafe by at least about 0.2 volts. 7. A method according to claim 1 comprising charging the battery with a voltage Vhv which is higher than the Vsafe by at least about 0.4 volts. 8. A method according to claim 1 comprising charging the battery with a voltage Vhv of from about 4.4 to about 5 volts. 9. A method according to claim 1 comprising charging the battery with a voltage Vhv of about 4.8 volts. 10. A method according to claim 1 wherein (b) comprises charging the battery with a voltage Vhv for from about 5 to about 50 seconds. 11. A method according to claim 1 wherein (c) comprises waiting for a time period that is at least about 10% of the time period used to charge the battery before measuring the open circuit voltage of the battery. 12. A method according to claim 1 wherein (c) comprises waiting for a time period of from about 1 to about 5 seconds after removing the voltage, before measuring the open circuit voltage of the battery. 13. A method of charging a rechargeable battery, the method comprising: (a) determining a safe charging voltage Vsafe that is the maximum open circuit voltage of the battery which provides a minimum battery capacity for a predetermined number of charge and discharge cycles of the battery;(b) charging the battery with a charging voltage Vhv which is higher than the Vsafe;(c) removing the charging voltage Vhv and measuring the open circuit voltage of the battery; and(d) performing one of the following: (i) when the open circuit voltage is less than Vsafe, repeating steps (b) through (d);(ii) when the open circuit voltage is substantially equal to Vsafe, reducing the charging voltage by from about 0.1 to 0.3 volts, and then, repeating steps (b) through (d); or(iii) ending the charging process when the charging voltage V_hd hv is equal to or less than Vsafe. 14. A method of charging a rechargeable battery, the method comprising: (a) determining a safe charging voltage Vsafe that is the maximum open circuit voltage of the battery which provides a minimum battery capacity for a predetermined number of charge and discharge cycles of the battery;(b) determining an internal resistance Rin of the battery;(c) charging the battery with a charging voltage Vhv which is higher than Vsafe;(d) monitoring the charging current Icrg of the battery; and(e) performing one of: (i) when Vhv−Icrg. X Rin=Vsafe, reducing the charging voltage Vhv by about 0.1 to about 0.3 volts, and repeating (c) through (e); or(ii) when the charging voltage Vhv is equal to or less than Vsafe, ending the charging process. 15. A battery charging apparatus for charging a battery, the apparatus comprising: (a) a voltage charger that provides a direct current voltage suitable for charging a battery;(b) a voltmeter to measure the open circuit voltage of the battery and generate a voltage signal;(c) an ammeter to measure a current of the battery charging circuit and generate a current signal; and(d) a controller to regulate the voltage charger in response to the voltage signal from the voltmeter, the current signal from the ammeter, and a determination of the internal resistance of the battery, the controller comprising computer-readable code to: (1) determine a safe charging voltage Vsafe that is the maximum open circuit voltage of the battery which provides a minimum battery capacity for a predetermined number of charge and discharge cycles of the battery;(2) operate the voltage charger to charge the battery with a voltage Vhv which is higher than the Vsafe;(3) disconnect the voltage charger and use the voltmeter to measure the open circuit voltage of the battery; and(4) repeat (2) and (3) when the open circuit voltage is less than Vsafe, and terminate the charging process when the open circuit voltage is substantially equal to or greater than Vsafe. 16. An apparatus according to claim 15 comprising a resistance meter to generate a battery resistance signal representative of the internal resistance of the battery, and wherein the controller receives the battery resistance signal. 17. An apparatus according to claim 15 wherein the controller determines the internal resistance of the battery from the voltage signal from the voltmeter and the current signal from the ammeter. 18. An apparatus according to claim 15 wherein the voltage charger comprises one of (i) an external AC source connected to a rectifier, (ii) a DC voltage source, or (iii) a photovoltaic cell. 19. A battery charging apparatus for charging a battery, the apparatus comprising: (a) a voltage charger that provides a direct current voltage suitable for charging a battery;(b) a voltmeter to measure the open circuit voltage of the battery and generate a voltage signal;(c) an ammeter to measure a current of the battery and generate a current signal; and(d) a controller to regulate the voltage charger in response to the voltage signal from the voltmeter, the current signal from the ammeter, and a determination of the internal resistance of the battery, the controller comprising computer-readable code to: (1) determining a safe charging voltage Vsafe that is the maximum open circuit voltage of the battery which provides a minimum battery capacity for a predetermined number of charge and discharge cycles of the battery;(2) operate the voltage charger to charge the battery with a charging voltage Vhv which is higher than the Vsafe;(3) remove the charging voltage and measure the open circuit voltage of the battery; and(4) perform one of the following: (i) when the open circuit voltage is less than Vsafe, repeat steps (2) through (4);(ii) when the open circuit voltage is substantially equal to Vsafe, reducing the charging voltage by from about 0.1 to 0.3 volts, and then, repeating (2) through (4); or(iii) ending the charging process when the charging voltage Vhv is equal to or less than Vsafe. 20. A battery charging apparatus for charging a battery, the apparatus comprising (a) a voltage charger that provides a direct current voltage suitable for charging a battery;(b) a voltmeter to measure the open circuit voltage of the battery and generate a voltage signal;(c) an ammeter to measure a current of the circuit and generate a current signal; and(d) a controller to regulate the voltage charger in response to the voltage signal from the voltmeter, the current signal from the ammeter, and a determination of the internal resistance of the battery, the controller comprising computer-readable code to: (1) determining a safe charging voltage Vsafe that is the maximum open circuit voltage of the battery which provides a minimum battery capacity for a predetermined number of charge and discharge cycles of the battery;(2) determine an internal resistance Rin of the battery;(3) operate the voltage charger to charge the battery with a charging voltage Vhv which is higher than Vsafe;(4) monitor the charging current Icrg of the battery; and(5) performing one of: (i) when Vhv−lcrg. ×Rin=Vsafe, reducing the charging voltage by about 0.1 to about 0.3 volts, and repeating (3) through (5); or(ii) when the charging voltage Vhv is equal to or less than Vsafe, ending the charging process. 21. A method according to claim 13 comprising providing a battery that includes a cathode comprising LiCoO2, and determining a safe charging voltage Vsafe that is at least one of the following: (i) from about 4.1 to about 4.2 volts; and(ii) provides a battery 5-hour rate discharge capacity of at least about 70% of the initial capacity after at least about 1000 charge and 80%-depth discharge cycles of the battery. 22. A method according to claim 13 wherein (b) comprises charging the battery with a voltage Vhv which is one of: (i) higher than the Vsafe by at least about 0.2 volts;(ii) higher than the Vsafe by at least about 0.4 volts; or(iii) from about 4.4 to about 5 volts. 23. A method according to claim 13 wherein (b) comprises charging the battery with a voltage Vhv for from about 5 to about 50 seconds. 24. A method according to claim 13 wherein (c) comprises waiting for a time period before measuring the open circuit voltage of the battery, the waiting time period being at least one of: (i) about 10% of the time period used to charge the battery; and(ii) from about 1 to about 5 seconds after removing the charging voltage from the battery. 25. A method according to claim 14 comprising providing a battery that includes a cathode comprising LiCoO2, and determining a safe charging voltage Vsafe that is at least one of the following: (i) from about 4.1 to about 4.2 volts; and(ii) provides a battery 5-hour rate discharge capacity of at least about 70% of the initial capacity after at least about 1000 charge and 80%-depth discharge cycles of the battery. 26. A method according to claim 14 wherein (b) comprises charging the battery with a voltage Vhv which is one of: (i) higher than the Vsafe by at least about 0.2 volts;(ii) higher than the Vsafe by at least about 0.4 volts; or(iii) from about 4.4 to about 5 volts. 27. A method according to claim 14 wherein (b) comprises charging the battery with a voltage Vhv for from about 5 to about 50 seconds. 28. A method according to claim 14 wherein (c) comprises waiting for a time period before measuring the open circuit voltage of the battery, the waiting time period being at least one of: (i) about 10% of the time period used to charge the battery; or(ii) from about 1 to about 5 seconds after removing the charging voltage from the battery. 29. An apparatus according to claim 19 comprising a resistance meter to generate a battery resistance signal representative of the internal resistance of the battery, and wherein the controller receives the battery resistance signal. 30. An apparatus according to claim 19 wherein the controller determines the internal resistance of the battery from the voltage signal from the voltmeter and the current signal from the ammeter. 31. An apparatus according to claim 19 wherein the voltage charger comprises one of (i) an external AC source connected to a rectifier, (ii) a DC voltage source, or (iii) a photovoltaic cell. 32. An apparatus according to claim 20 comprising a resistance meter to generate a battery resistance signal representative of the internal resistance of the battery, and wherein the controller receives the battery resistance signal. 33. An apparatus according to claim 20 wherein the controller determines the internal resistance of the battery from the voltage signal from the voltmeter and the current signal from the ammeter. 34. An apparatus according to claim 20 wherein the voltage charger comprises one of (i) an external AC source connected to a rectifier, (ii) a DC voltage source, or (iii) a photovoltaic cell. 35. A method of charging a rechargeable battery, the method comprising: (a) determining a safe charging voltage Vsafe that is the maximum open circuit voltage of the battery which provides a minimum battery capacity for a predetermined number of charge and discharge cycles of the battery;(b) determining an internal resistance Rin of the battery;(c) charging the battery with a charging voltage Vhv which is higher than Vsafe while monitoring the charging current lug of the battery, until the charging current lug is equal to or less than a cutoff current lc, where lc=(Vhv −Vsafe)/Rin;(d) reducing the charging voltage Vhv to a reduced charging voltage when the charging current is equal to or less than lc. 36. A method according to claim 35 further comprising: (e) recalculating the cutoff current lc from the reduced charging voltage to determine a new cutoff current;(f) continuing charging the battery with the reduced charging voltage until the new cutoff current is reached;(g) repeating steps (c) to (f) and ending the charging process when the charging voltage Vhv is equal to or less than Vsafe. 37. A method according to claim 35 wherein in (c), Vhv is from about 4.4V to about 5V. 38. A method according to claim 35 wherein in (a), Vsafe is typically from about 4.1 V to about 4.4V. 39. A method according to claim 35 wherein in (c) the charging voltage Vhv is higher than Vsafe but not high enough to cause a phase change in a cathode of the battery. 40. A method of charging a battery, the method comprising: (a) determining a safe charging voltage Vsafe that is the maximum open circuit voltage of the battery which provides a minimum battery capacity for a predetermined number of charge and discharge cycles of the battery;(b) charging the battery with a charging voltage Vhv which is higher than the Vsafe;(c) measuring an open circuit voltage of the battery after removing the charging voltage Vhv and waiting for a time period; and(d) repeating steps (b) and (c) when the measured open circuit voltage is less than Vsafe or terminating charging when the open circuit voltage is substantially equal to or greater than Vsafe. 41. A method according to claim 40 wherein (b) comprises charging the battery with a charging voltage Vhv for a time period, and (c) comprises measuring an open circuit voltage of the battery after removing the charging voltage Vhv and waiting for a time period that is at least about 10% of the time period for charging the battery. 42. A method according to claim 40 wherein (c) comprises waiting for a time period of from about 1 to about 5 seconds after removing the voltage Vhv, before measuring the open circuit voltage of the battery. 43. A method according to claim 40 comprising reducing the charging voltage Vhv by from about 0.1 to about 0.3V, each time steps (b) to (d) are repeated. 44. A method of charging a battery, the method comprising: (a) determining a safe charging voltage Vsafe that is the maximum open circuit voltage of the battery which provides a minimum battery capacity for a predetermined number of charge and discharge cycles of the battery;(b) charging the battery with a charging voltage Vhv which is higher than the Vsafe;(c) measuring the open circuit voltage of the battery after removing the charging voltage Vhv and waiting for a time period;(d) repeating steps (b) and (c) and stopping charging when the measured open circuit voltage is greater than or equal to Vsafe for another time period; and(e) charging the battery with a voltage that is Vsafe until the battery current drops to a preset value. 45. A method according to claim 44 wherein the preset value is battery current is 0.1C-rate. 46. A method according to claim 1 wherein the battery comprises a cathode, and wherein (b) comprises charging the battery with a charging voltage Vhv which is selected in relation to the thickness of the thickness of the cathode. 47. A method of charging a battery, the method comprising: (a) determining a safe charging voltage Vsafe for the battery that is capable of providing at least a predetermined battery capacity after a predetermined number of charge and discharge cycles of the battery; and(b) charging the battery with a charging voltage Vhv;(c) removing the charging voltage Vhv, and after a time period, measuring the open circuit voltage of the battery; and(d) terminating charging of the battery when the measured open circuit voltage is substantially equal to or greater than Vsafe. 48. A method according to claim 47 wherein (c) comprises waiting for a time period that is at least about 10% of the time period used to charge the battery.