Metal-doped nickel oxide active materials
View Patent ↗A primary alkaline battery includes a cathode having an alkali-deficient nickel (IV)-containing oxide including metals such as Ni, Co, Mg, Al, Ca, Y, Mn, and/or non-metals such as B, Si, Ge or a combination of metal and/or non-metal ions as stabilizing dopants; a combination of metal ions as dopants; an anode; a separator between the cathode and the anode; and an alkaline electrolyte. The battery can be pre-discharged within one hour after assembly to decrease the open circuit voltage.
1. A method of making a pre-discharged primary alkaline battery, comprising:
(a) partially discharging an assembled primary alkaline battery at a constant current discharge rate from 5 mA/g to 100 mA/g of active material,
the partially discharging of the assembled primary alkaline battery being completed within about one hour after assembly of the primary alkaline battery is completed to result in a partially discharged primary alkaline battery;
(b) maintaining the partially discharged primary alkaline battery for a period of time ranging from 1 to 24 hours at a temperature in the range of 25 to 70° C. to result in a pre-discharged primary alkaline battery;
wherein the pre-discharged primary alkaline battery has an open circuit voltage value of less than or equal to 1.75 V at 25° C. and
said pre-discharged primary alkaline battery comprises:
a cathode comprising an oxide having a formula A x Ni 1-y-z-x Co y M a z M b w O 2 ;
an anode;
a separator between the cathode and the anode; and
an alkaline electrolyte,
wherein
A is an alkali metal;
M a is a metal dopant, the metal dopant comprising Co, Mg, Al, Co, Mn, or Y;
M b is a non-metal dopant, the non-metal dopant comprising B, Si, or Ge;
0≦x≦0.2.
w is 0, or 0≦w≦0.02; and
0.02≦y+z≦0.25.
2. The method of claim 1 , wherein the pre-discharged primary alkaline battery has a capacity retention of at least 95 percent of the capacity of a battery discharged within 24 hours after manufacture, after storage for at least one week at 25° C.
3. The method of claim 1 , wherein the pre-discharged primary alkaline battery has a decrease in oxygen evolution of at least 50% compared to a freshly assembled battery.
4. The method of claim 1 , wherein the pre-discharged primary alkaline battery has an open circuit voltage value of from 1.65 to 1.75 V at 25° C.
5. The method of claim 1 , wherein the assembled primary alkaline battery is partially discharged by 15 percent or less of a total battery design capacity.
6. The method of claim 1 , wherein the assembled primary alkaline battery is partially discharged by 10 percent or less of a total battery design capacity.
7. The method of claim 1 , wherein the assembled primary alkaline battery is partially discharged by 7.5 percent or less of a total battery design capacity.
8. The method of claim 1 , wherein the assembled primary alkaline battery is partially discharged by five percent or less of a total battery design capacity.
9. The method of claim 1 , wherein partially discharging the assembled primary alkaline battery is performed in discrete steps.
10. The method of claim 1 , wherein partially discharging the assembled primary alkaline battery is performed at 25° C.
11. The method of claim 1 , wherein partially discharging the assembled primary alkaline battery is performed at a temperature of from 20 to 30° C.