Second Generation Aqueous Electrolyte Electrochemical Cells for Scaled Stationary Energy Storage

The design and function of next generation aqueous electrolyte dual-intercalation energy storage devices and systems will be discussed.  These system use relatively unexplored electrode interactions that exploit muti-cation reactions (eg lithium, sodium and proton interactions all can contribute to the energy storage function). The core device uses a configuration wherein the active anode material consists of a blend of carbon-coated NaTi₂(PO₄)₃ and activated carbon and the cathode is cubic spinel l-MnO₂ that has resident lithium.  The electrolyte is a blend of Li⁺ and Na⁺ and hydrogen (at some states of charge) cation species, with SO₄^- and OH^- (at some states of charge) as the countering anions, solvated in an initially neutral pH aqueous electrolyte. 

Improvements to the original large-format devices first disclosed in 2011 will be disclosed, and data will be presented showing that large scale industrially packaged batteries with over 3000 Wh in capacity have be produced and qualified.  Data showing the relationship between electrode thickness, current collector resistance, and overall battery performance will be shown. Systems containing packs of these batteries in the multi-kWh range have been effectively implemented in field-testing around the world.  These applications include support for both smaller off-grid applications with bus voltages in the in the 20 to 100 V range, as well as, grid compatible systems with bus voltages in excess of 1000 V.