QuantumScape prototype Li-metal cell retains 95% discharge energy over 1,000 cycles

QuantumScape, a US battery company, has announced that its 24-layer A0 prototype cell retained over 95% discharge energy over 1,000+ full cycle equivalents in lab testing.

QuantumScape stated that no automotive-format lithium-metal battery has exhibited this discharge energy retention across a similar cycle count at room temperature and modest pressure. The single-layer cells that QuantumScape reported in Q3 2022 have now achieved between 1,500 and 2,000 cycles to ~80% discharge energy retention with zero externally applied pressure, which is 1.5-4 times the life cycle of many consumer electronics, according to the company. 

QuantumScape has named the proprietary, hybrid cell format of its planned commercial product FlexFrame. FlexFrame uses pouch and prismatic cell designs to address the lithium metal expansion during charging/discharging and pack the same number of layers with more energy per layer into a slimmer package for EVs.

“Together with the higher-loading cathode results reported in our Q1 2023 shareholder letter, we have now separately demonstrated three key aspects of our production-intent cell design: 24 layers, higher cathode loading (~5mA/cm²), and our new cell format. When these aspects are combined with improvements to packaging efficiency and manufacturing process control and automation for improved reliability, it forms the core of our first commercial product, QSE-5. QSE-5 is designed to have ~5 amp-hours (Ah) of capacity; for reference, the 2170 battery used in several leading EV models has a typical capacity of ~4.5–5 Ah,” QuantumScape said in its Q3 fiscal 2023 letter to shareholders.

Source: QuantumScape via Green Car Congress