MECHANICAL PULVERIZATION OF COBALT-FREE NICKEL-RICH CATHODES
The present disclosure relates to mitigation strategies to limit particle fracture and surface degradation caused by air instability. Some embodiments include cobalt-free nickel-rich NMA (LiNi 0.9 Mn 0.5 Al 0.05 O 2 ) being ball-milled to effectively “pre-crack” the secondary particles into their primary constituents or single crystallites. These NMA particles may be coated with lithium phosphate and/or phosphoric acid. After approximately 100 cycles, these pulverized NMA particles showed delay voltage decay and approximately double the discharge capacity compared to traditional pristine NMA cathode materials during high-voltage cycling.
1 . A method comprising:
pulverizing a pristine LiNi 0.9 Mn 0.5 Al 0.05 O 2 (NMA) cathode material resulting in a pulverized NMA cathode material; and
applying a coating on the pulverized NMA cathode material resulting in a coated pulverized NMA cathode material.
2 . The method of claim 1 , further comprising:
combining the coated pulverized NMA cathode material with the pristine NMA cathode material resulting in a bimodal NMA cathode material.
3 . The method of claim 2 , further comprising:
utilizing the bimodal NMA cathode material in a lithium-ion battery.
4 . The method of claim 3 , wherein:
the lithium-ion battery retains at least 50% of its capacity retention after 100 cycles at C/3.
5 . The method of claim 4 , wherein:
the lithium-ion battery retains at least 80% of its capacity retention after 100 cycles at C/3.
6 . The method of claim 2 , wherein:
the bimodal cathode material comprises the pristine NMA cathode material and the coated pulverized NMA cathode material combined in a ratio in the range of about 50:50 to about 95:5.
7 . The method of claim 6 , wherein:
the bimodal cathode material comprises the pristine NMA cathode material and the coated pulverized NMA cathode material combined in a ratio of approximately 80:20.
8 . The method of claim 1 , further comprising:
utilizing the coated pulverized NMA cathode material in a lithium-ion battery.
9 . The method of claim 1 , wherein the pulverizing comprises:
grinding the pristine NMA cathode material using a ball mill.
10 . The method of claim 1 , wherein the pulverizing comprises:
grinding the pristine NMA cathode material using a roller mill.
11 . The method of claim 1 , wherein the pulverizing comprises:
crushing the pristine NMA cathode material.
12 . The method of claim 1 , wherein the applying comprises:
exposing the pulverized NMA cathode material to phosphoric acid, wherein:
the exposing results in the coating comprising lithium phosphate to be present on the pulverized NMA cathode material.
13 . The method of claim 1 , wherein the applying comprises:
using vapor deposition to deposit the coating on the pulverized NMA cathode material.
14 . The method of claim 1 , wherein the coating comprises at least one of lithium phosphate, aluminum oxide, or aluminum fluoride.
15 . A lithium-ion battery device comprising:
a cathode comprising a coated pulverized NMA cathode material.
16 . The device of claim 15 , wherein:
the lithium-ion battery retains at least 50% of its capacity retention after 100 cycles at C/3.
17 . The device of claim 16 , wherein:
the lithium-ion battery retains at least 80% of its capacity retention after 100 cycles at C/3.
18 . The device of claim 15 , wherein:
the cathode further comprises a pristine NMA cathode material, resulting in a bimodal cathode material.
19 . The device of claim 18 , wherein:
the bimodal cathode material comprises the coated pulverized NMA cathode material and the pristine NMA cathode material in a ratio in the range of about 50:50 to about 95:5.
20 . The device of claim 18 , wherein:
the bimodal cathode material comprises the coated pulverized NMA cathode material and the pristine NMA cathode material in the ratio of approximately 80:20.