Niobium in Batteries

Niobium in batteries looks at the high level addition of this element and some of the claimed and measured improvements to the battery cells as a result.

There are a lot of companies and startups looking at the addition of Niobium to battery chemistry to:

• improve stability
• increase capacity
• coatings
• faster charging

This is being added to anode and cathode materials, all in research. First perhaps we should start with Toshiba as they have a solid reputation in LTO technology and they are building on this with NTO.

Niobium-Based Anode

Toshiba Super Charge ion Battery (SCiB) [5] are developing a Niobium Titanium Oxide anode that will have improved performance over the current LTO products:

• 20,000 cycle life
• 0 to 90% SoC in 6 minutes
• 12kW/litre
• 71% capacity retention at -30°C
• Usable SoC window 0 to 100%

Downside:

• Energy density:
  • ~150Wh/kg – compared to ~265Wh/kg for NMC811
  • ~300Wh/litre – compared to ~750Wh/litre for NMC811

Cycle life, charging and cold performance are all improved, but the energy density (both gravimetric and volumetric) is significantly lower than most other Lithium-ion chemistry.

NTO has roughly three times higher theoretical volume capacity density than LTO while providing the advantages of LTO such as long life and rapid charging.

Using Niobium Titanium Oxide (NTO) as a next-generation anode material, Toshiba

Echion Technologies [3] make some significant claims with their Niobium Oxide technology:

• 0 to 100% charge in 6 min or less
• Twice the volumetric capacity of LTO anodes (x2)
• Safe operating voltage
• 1000’s of cycles demonstrated
• Low cost

NEI Corporation [9] offer Niobium oxide coated copper electrodes: Niobium Oxide (Nb₂O₅) is a new electrode material with pseudocapacitive charge storage being introduced to the market for the first time as a potential anode material. It is capable of exceptionally high rate charge as well as discharge (6 – 10C), with good cycling stability (1,000 – 3,000 cycles) and minimal heat generation during high-rate charge-discharge. The unique architecture of the oxide material enables rapid lithium diffusion on a macro and micro-scale enabling enhanced rate performance.

Niobium-Based Cathodes

Nb-NMC811 Cathode

nanoOne – Phase One [6] applied the niobium coating technology to NMC811 cathode active material and the next two phases will focus on the niobium coating of even higher nickel NMC. This will include scaling of the One-Pot coating technology to demonstrate commercial viability and validate the supply chain. 

Nb-NCA85

Un-Hyuck Kim et al [8] show: “The Nb dopant (1 mol%) elongates the primary particles and aligns them in the radial direction, creating a configuration that effectively dissipates the abrupt internal strain caused by H2↔H3 phase transitions near the charge end. The negation of the internal strain substantially improves the long-term cycling stability achieved by the Nb-doped NCA85 cathode; it retains 90% of its initial capacity after 1000 cycles while an undoped cathode retains 57.3%. Moreover, the enhanced mechano-chemical stability of the Nb-doped NCA85 cathode enables fast charging; accordingly, the Nb-doped NCA85 cathode cycles stably for 500 cycles even when charged at 3C”

Nb-NMC9055 Cathode

There is a drive to further reduce the amount of Cobalt in batteries and hence the move towards 90% Nickel.

Fengxia Xin et al [1] show: “The Nb modification on NMC 9055 significantly improved the capacity retention, providing 99.7% in the 2.1% Nb-NMC 9055 electrode compared to 75.3% in the unmodified NMC 9055 after 200 cycles.”

“Accompanied with the stable capacity retention was almost zero voltage fading.”

The conclusion from the paper: “Nb modification on NMC 9055 enables long-term cycling stability, good capacity retention, and excellent deep charge/discharge voltage, thus providing a strategy to solve cycling fading problem (capacity and voltage decays with cycling) of high nickel NMC materials.”

References:

1. Fengxia Xin, Anshika Goel, Xiaobo Chen, Hui Zhou, Jianming Bai, Sizhan Liu, Feng Wang, Guangwen Zhou, and M. Stanley Whittingham, Electrochemical Characterization and Microstructure Evolution of Ni-Rich Layered Cathode Materials by Niobium Coating/Substitution, Chem. Mater. 2022, 34, 17, 7858–7866
2. The NorthEast Center for Chemical Energy Storage, Binghampton University, State University of New York
3. Niobium Oxide Anode, Echion Technologies
4. Niobium in Li-ion batteries, Niobium Tech
5. SCiB – Toshiba
6. Nano One Enters into a Co-Development Agreement with Niobium Producer CBMM, nanoOne
7. Echion and Topsoe publishes Whitepaper showcasing high performance, cobalt-free, 3V LNMO-XNO™ cell system, Echion
8. Un-Hyuck Kim, Jeong-Hyeon Park, Assylzat Aishova, Rogério M. Ribas, Robson S. Monteiro, Kent J. Griffith, Chong S. Yoon, Yang-Kook Sun, Microstructure Engineered Ni-Rich Layered Cathode for Electric Vehicle Batteries, Advanced Energy Materials
9. Niobium Oxide coated sheets, NEI Corporation