Li-S battery company OXIS Energy reports 300 Wh/kg and 25 Ah cell, predicting 33 Ah by mid-2015, 500 Wh/kg by end of 2018
UK-based Lithium-sulfur battery company OXIS Energy (earlier post) reported developing a Lithium-sulfur cell achieving in excess of 300 Wh/kg. In addition, OXIS has achieved an increase in cell capacity to 25 Ah—a twelve-fold improvement in 18 months. OXIS predicts it will achieve a cell capacity of 33Ah by mid-2015. The company says that vehicle manufacturers are already reviewing and evaluating the cell technology.
The OXIS scientific team expects to achieve a goal of an energy density in excess of 400 Wh/kg by the end of 2016 and in excess of 500Wh/kg by the end of 2018. OXIS CEO Huw Hampson-Jones says that the company is on schedule to release commercial cells for use in applications in the USA and Europe in 2015.
The cells continue to display the enhanced safety features that characterise Li-S with superior safety performance attained in a barrage of industry-standard tests.
OXIS is collaborating with leading European companies and universities to harness the new material developments to enhance energy density and cyclability. OXIS says that the modeling techniques being perfected allow the OXIS scientific team to predict and improve battery performance and operating conditions pertaining to a number of applications including automotive applications.
Achieving the automotive targets is accelerating developments for additional markets such as marine, UAVs, energy storage and military applications that require ultra-light weight battery solutions. These may lead to spin-off projects and additional collaborations in the future. In August, for example, OXIS Energy and Multi Source Power technologies (MSP) formed a partnership to develop Li-sulfur batteries for marine applications.
Oxis Lithium-sulfur cells comprise a Lithium metal anode; sulfur-based cathode; a ceramic lithium sulfide passivation layer; and a non-flammable electrolyte protecting the lithium metal. OXIS cells have a 100% available Depth-of-Discharge and cannot be damaged by over-discharge.
Cycle life is one of the major challenges of Li-S batteries; OXIS reported its Li-S cells in 2012 could be cycled more than 1,000 times (80% Beginning-of-Life), and expects to be able to reach around 2000 cycles before the capacity reduces to 80% BoL.