The specific capacity of NCM622, particularly in its enhanced or modified forms, can reach approximately 199.1 mAh g−1. This value is observed under specific test conditions, such as a discharge rate of 0.1 C.
Understanding NCM622 Specific Capacity
NCM622, a type of Lithium Nickel Cobalt Manganese Oxide (LiNiCoMnO2) cathode material, is widely used in lithium-ion batteries due to its balance of energy density, power capability, and cycle life. Its specific capacity, a measure of how much charge it can store per unit of mass, is a crucial performance indicator.
Key Characteristics and Performance
Research continually aims to improve the electrochemical performance of NCM622. For instance, studies show that modified NCM materials, developed within the context of NCM622 research, can achieve notable capacities.
- Discharge Specific Capacity: A final C–NCM material, closely related to NCM622 and investigated for enhanced electrochemical performance, has demonstrated a high discharge specific capacity of 199.1 mAh g−1 when discharged at a rate of 0.1 C. This indicates its excellent capability to store and release charge effectively under low current conditions.
- Cycle Stability: Beyond initial capacity, the material's ability to retain capacity over many charge-discharge cycles is vital. The mentioned C-NCM material also exhibited a cycle retention rate of 79.7% after 200 cycles at a higher rate of 1 C, signifying good stability.
Factors Influencing Specific Capacity
The specific capacity of NCM622 can vary based on several factors:
- C-rate: The discharge rate (C-rate) significantly impacts measured capacity. Lower C-rates (slower discharge) generally allow for higher reported capacities, as the active material has more time to fully react.
- Material Modification: Surface coatings, doping, or composite structures (like the C-NCM material mentioned) can enhance ion diffusion, structural stability, and ultimately, specific capacity.
- Electrolyte Composition: The type of electrolyte and its additives can influence the intercalation/deintercalation kinetics of lithium ions, affecting capacity and rate performance.
- Operating Temperature: Battery performance, including capacity, is temperature-dependent.
Performance Overview of NCM622 (Example)
| Performance Metric | Value | Conditions | Reference/Context |
|---|---|---|---|
| Discharge Specific Capacity | 199.1 mAh g−1 | At 0.1 C | Observed in a C-NCM material, a derivative or enhanced form of NCM, investigated in studies that include NCM622. For more context, specific capacity vs. voltage curves for NCM622 are often analyzed in such research. For additional details, see researchgate.net. |
| Cycle Retention Rate | 79.7% | After 200 cycles at 1 C | Indicates the stability of the material over repeated usage. |
Practical Implications
The high specific capacity of NCM622 makes it a desirable cathode material for:
- Electric Vehicles (EVs): Contributing to longer driving ranges.
- Portable Electronics: Enabling extended usage times for devices.
- Grid Storage: Providing efficient energy storage solutions.
Ongoing research continues to refine NCM622 and related materials to push the boundaries of specific capacity, cycle life, and safety for next-generation battery technologies.
