Hanyang University And BMW Develops 350 Wh/kg Lithium-Ion Cells
A research team from the Hanyang University BMW Group has developed high energy dense lithium-ion battery cells, with a capacity of 350 Wh/kg.
The new “fully operational, practical” cells use carbon-nanotube-Si composite anode and NCM concentration gradient cathode.
According to the article, the cell also has excellent capacity retention after 500 cycles at 1 C rate (about 80% capacity left), which should make it usable in EVs, given the high density (which would theoretically translate into longer range applications)
We are not sure when we could actually see a 300 mile range BMW i3, but it’s good to know that there is an idea to achieve such a range.
“A fully operational practical Li-rechargeable battery system delivering unprecedented high energy density with excellent cycle life was proposed using the state-of-the-art cathode and anode technologies.
Based on the simple ball-milling process, a carbon nanotube (CNT)-Si composite anode with extremely stable long-term cycling, while providing a discharge capacity of 2364 mAh g-1 at a tap density of 1.1 g cm-3, was developed.
For cathode, a two-sloped full concentration gradient (TSFCG) Li[Ni0.85Co0.05Mn0.10]O2 cathode, designed to obtain maximum possible discharge capacity by having Ni-enrich core and to simultaneously ensure high chemical and thermal stability by having outer Mn-enriched layer, yielded a discharge capacity of 221 mAh g-1. Integrating the CNT-Si composite and the TSFCG cathode in a full cell configuration, the full cell generated an energy density of 350 Wh kg-1 with excellent capacity retention for 500 cycles at 1 C rate, satisfying the energy density limit imposed by the drive range requirement for EVs. The proposed battery system satisfied the demands for energy storage for vehicle applications in terms of energy density, power and cycle life.”