ISRO’s VSSC Achieves Milestone with Flight Demonstration of High Energy Density Li-ion Cells.

The Vikram Sarabhai Space Centre (VSSC) under the Indian Space Research Organisation (ISRO) has achieved a significant milestone by successfully qualifying 10 Ah Silicon–Graphite anode-based high energy density Li-ion cells. Positioned as a low-weight and low-cost alternative to existing cells, these cells have undergone a successful flight demonstration by powering a resistive load on-board the POEM-3 platform of PSLV-C58.

Distinguished by its use of Si-Graphite composite as the anode material, this Li-ion cell surpasses conventional cells that employ pure graphite, accommodating more Lithium ions for a given unit mass of anode material and enhancing overall energy density. The innovative cell design also incorporates cost-effective hardware readily available in the market, along with a crimped sealing-based design that significantly reduces hardware and fabrication costs.

The energy density of these Silicon High Energy Li-ion cells is an impressive 190 Wh/kg, operating within a voltage range of 4.2 to 2.8 V, outperforming traditional Lithium-ion cells (157 Wh/kg). During the flight demonstration, the battery system exhibited robust performance, working for 21 hours in 15 orbits and delivering a capacity of 8.9 Ah, with a final drained voltage of 0.4 V.

VSSC, known for its rigorous qualification processes, subjecting new systems to thorough testing and flight demonstrations, demonstrated the capability of these cells to withstand and perform in the harsh space environment through the POEM experiment.

Buoyed by the successful performance, these high-energy density Li-ion cells are poised to be integrated into upcoming operational missions, promising a substantial 35-40% reduction in battery mass. The versatility of these cells extends to both space and ground applications, showcasing a promising leap in energy-efficient technology for space exploration and beyond.