High-power density lithium-ion (Li-ion) batteries with higher energy density are increasingly needed in applications such as communications, power tools, robotics, unmanned aerial vehicles (UAV), and hybrid electric vehicles (HEV) and plug-in hybrid electric vehicles. The state-of-the-art Li-ion batteries have encountered substantial reduction in power performance at temperatures below -30 oC and reduced cycle and storage life at temperatures above 55 oC. Furthermore, under shorting and overcharge conditions, the current Li-ion batteries will undergo thermal runaway and become dangerous. The energy density of the current Li-ion chemistries has reached their limits, 200 to 250 Wh/kg, while safer and higher energy density Li-ion batteries are still desirable.
Research and development activities include investigation of factors limiting the charge-transfer kinetics at the electrode/electrolyte interfaces, understanding solid-electrolyte interface (SEI) formation resulting from the electrolyte and electrode reactions for guiding materials development, development of high voltage cathode for increased energy density, and development of compatible high voltage electrolytes including synthesis, characterization, and evaluation of new solvents and salts for improved electrochemical performance and safety.
Borodin, O, Behl W, Jow TR: Journal of Physical Chemistry C 117: 8661, 2013
Jow TR, Marx MB, Allen JL: Journal of the Electrochemical Society 59(5): A604, 2012
Allen JL, Jow TR, Wolfenstine J: Journal of Power Sources 196: 8656, 2011
Electrochemistry; Lithium-ion-batteries; Electrodes; Electrolytes; Lithium mixed metal oxides; Lithium transition metal phosphate; Electrode-electrolyte interactions;