Abstract: A method of discharging a spent lithium-ion (Li-ion) battery may include contacting external electrodes of the spent Li-ion battery to a discharging solution. The discharging solution including an aqueous solution of salts having a same anion and a redox couple as cations. The redox couple includes a first cation of a metal having a first oxidation state and a second cation of the same metal having a second oxidation state different from the first oxidation state.

Abstract: Devices and techniques are generally described for a speech processing procurement system. In various examples, recommendations may be provided by back-end systems. The recommendations may be ranked by a machine learning model, and may be sorted and filtered for a particular output device. Various voice guidance workflows may be invoked through user interaction with a speech processing procurement system. The workflows may be used to surface pre-recorded voice memos and/or to determine recommendations based on dynamically updated procurement policies.