High-tech company launches innovative battery cell technology specifically for the automotive sector
SVOLT Energy Technology Co., Ltd. (SVOLT), a global high-tech company headquartered in China, first announced its battery cells with cobalt-free cell chemistry at the International Motor Show (IAA) in September 2019. The first cell variants can now be ordered. SVOLT President & General Manager Hongxin Yang announced this at the first SVOLT Battery Day, which took place in Wuxi in mid-December 2020.
Globally, the system provider is initially offering two sizes of the innovative nickel-manganese battery cells (NMX). These do not require the heavy metal cobalt, which is otherwise used to thermally stabilize high-nickel battery cells (NCM). Serial production of the new products is scheduled to start in June 2021 at the factory in Jintan, China. By the end of 2023, the new batteries may also be produced at the planned factory in Saarland, Germany.
Cobalt-free battery cell in two sizes
Among other variants, cobalt-free NMX battery cells with 115Ah and an energy density of 245 Wh/kg can now be ordered in MEB format (33.4 x 220 x 102.5 mm). Their
voltage is 3.74V and their capacity is 430 Wh. This means that the 115Ah variant of the NMX battery from SVOLT achieves an effectively usable capacity of 396 Wh. This cell variant is expected to be available from the second quarter of 2021.
A cobalt-free cell variant with 226Ah and an energy density of 240 Wh/kg can also be ordered and is expected to be available from the fourth quarter of 2021. The 226Ah version is SVOLT’s own cell format L6 (21.5 x 574 x 118 mm). L-cells are long battery cells in a thin prismatic design with electrodes and degassing valves positioned at the sides.
Elimination of cobalt makes battery cells more sustainable and affordable
SVOLT’s cobalt-free NMX cells are not only significantly more sustainable, they are also around five percent cheaper than classic high-nickel batteries. This is made possible thanks to the reduced nickel content, on the one hand, and due to the complete elimination of the heavy metal cobalt – one of the most expensive and controversial cathode elements – on the other hand. These factors make the battery cells particularly suitable for the broad middle-range market. At the same time, SVOLT’s products achieve an energy density that is just five percent below that of comparable NCM battery cells.
The new battery cells consist of 75 percent nickel and 25 percent manganese and are stabilized by using doping and coating processes developed by SVOLT. NMX cells achieve higher thermal stability and overall safety than NCM cells.
Long life and high performance thanks to innovative cathode material
With this new technology, SVOLT has also succeeded in significantly improving the life cycle and the calendar life of NMX cells compared to conventional NCM battery cells. This means more than 2,500 charging cycles, among other benefits. The company developed a special cathode material, based on a single crystal with a wafer-thin surface coating (nano-coating), consisting of only a few hundred molecules to achieve a long-lived cobalt–free NMX battery cell.
Using this single crystal approach, SVOLT reduces one of the main causes of ageing in electric vehicle batteries: the formation of micro-cracks and fractures in the active cathode material and thus wear on the cell. At the same time, the coating, which is only a few nanometers thick, protects the surface of the used cathode material against secondary reactions with the electrolyte. In this way, SVOLT significantly slows down cell ageing in its NMX battery cells.
SVOLT also relies on a supplementary doping process in which foreign atoms, the so-called doping material, are inserted into the cathode material. By doing so, SVOLT not only succeeds in stabilizing NMX cells without cobalt, but also in increasing the mobility of the lithium ions in the cathode as well as conductivity. This helps to improve the performance of the battery.
The two NMX cell sizes from SVOLT can now be ordered worldwide. Additional NMX cell variants are planned in the near future.
Images courtesy of SVOLT