Embodiments described herein relate to semi-solid electrodes with carbon additives, and methods of making the same. In some embodiments, a semi-solid electrode, can include about 35% to about 75% by volume of an active material, about 0.5% to about 8% by volume of a conductive material, and about 0.2% to about 5% by volume of a carbon additive. The carbon additive is different from the conductive material. The active material, the conductive material, and the carbon additive are mixed with a non-aqueous electrolyte to form the semi-solid electrode. In some embodiments, the carbon additive includes carbon nanofibers, vapor-grown carbon fibers (VCGF), carbon nanotubes (CNT's), single-walled carbon nanotubes (SWNT's), and/or multi-walled carbon nanotubes (MWNT's). In some embodiments, the semi-solid electrode can have a yield stress of less than about 100 kPa.

A flow battery system and methods are provided for eliminating crossover issues of active materials in redox flow batteries. A solid adsorbent with large specific surface area is disposed in an electrolyte of at least one half-cell, in contact with the electrolyte. During a charging process, the active material in a charged state is captured and stored on surfaces of the adsorbent, so that concentrations of the active material in the electrolyte in the charged state is reduced and the crossover is inhibited. During a discharging process, the active material is desorbed from the adsorbent to the electrolyte and pumped into the stack for reaction. The flow battery stack can have a microporous membrane separator. The electrolyte of the flow battery includes zinc iodide as active material and polyethylene glycol (PEG) as an additive.

A flow battery system and methods are provided for eliminating crossover issues of active materials in redox flow batteries. A solid adsorbent with large specific surface area is disposed in an electrolyte of at least one half-cell, in contact with the electrolyte. During a charging process, the active material in a charged state is captured and stored on surfaces of the adsorbent, so that concentrations of the active material in the electrolyte in the charged state is reduced and the crossover is inhibited. During a discharging process, the active material is desorbed from the adsorbent to the electrolyte and pumped into the stack for reaction. The flow battery stack can have a microporous membrane separator. The electrolyte of the flow battery includes zinc iodide as active material and polyethylene glycol (PEG) as an additive.

An all-solid secondary battery includes: a positive electrode including a positive electrode active material layer; a negative electrode including a negative electrode current collector and a negative electrode active material layer on the negative electrode current collector; and a solid electrolyte layer between the positive electrode active material layer and the negative electrode active material layer, wherein the negative electrode active material layer includes first particles including a carbon material, and second particles including a metallic material that does not alloy with lithium metal.

An all-solid secondary battery includes: a positive electrode including a positive electrode active material layer; a negative electrode including a negative electrode current collector and a negative electrode active material layer on the negative electrode current collector; and a solid electrolyte layer between the positive electrode active material layer and the negative electrode active material layer, wherein the negative electrode active material layer includes first particles including a carbon material, and second particles including a metallic material that does not alloy with lithium metal.

An electrochemical cell is provided herein as well as methods for preparing electrochemical cells. The electrochemical cell includes a negative electrode and a positive electrode. The negative electrode includes a prelithiated electroactive material including a lithium silicide. Lithium is present in the prelithiated electroactive material in an amount corresponding to greater than or equal to about 10% of a state of charge of the negative electrode. The electrochemical cell has a negative electrode capacity to positive electrode capacity for lithium (N/P) ratio of greater than or equal to about 1, and the electrochemical cell is capable of operating at an operating voltage of less than or equal to about 5 volts.

An electrochemical cell is provided herein as well as methods for preparing electrochemical cells. The electrochemical cell includes a negative electrode and a positive electrode. The negative electrode includes a prelithiated electroactive material including a lithium silicide. Lithium is present in the prelithiated electroactive material in an amount corresponding to greater than or equal to about 10% of a state of charge of the negative electrode. The electrochemical cell has a negative electrode capacity to positive electrode capacity for lithium (N/P) ratio of greater than or equal to about 1, and the electrochemical cell is capable of operating at an operating voltage of less than or equal to about 5 volts.

Filled carbon nanotubes (CNTs), methods of synthesizing the same, and lithium-ion batteries comprising the same are provided. In situ methods (e.g., chemical vapor deposition techniques) can be used to synthesize CNTs (e.g., multi-walled CNTs) filled with metal sulfide nanowires. The CNTs can be completely (or nearly completely) and continuously (or nearly continuously) filled with the metal sulfide fillers up to several micrometers in length. The filled CNTs can be synthesized on a carbon substrate. A lithium-ion battery can comprise a cathode, an anode comprising filled CNTs as described herein, and an electrolyte in contact with the cathode and/or the anode.

A method of manufacturing a three-dimensional electrochemical lithium battery includes forming a first electrode on an underlying layer comprising aerosolizing a first ink formulation comprising a slurry including nanoparticles or microparticles of a first active material and a binder, and depositing the slurry onto the underlying layer to form a first electrode layer. A permeable separator layer is formed on the first electrode by aerosolizing a polymer precursor solution, exposing the aerosolized polymer precursor solution to a first activating radiation source to form partially cured polymer spheres in the aerosolized stream, focusing and directing the aerosolized stream onto a substrate to form the permeable separator layer of the partially cured polymer spheres, and exposing the partially cured polymer spheres on the substrate to a second activating radiation source to fully cure the partially cured polymer spheres. A second electrode is formed on the permeable separator layer by aerosolizing a second ink formulation comprising a slurry including nanoparticles or microparticles of a second active material and a binder, and depositing the slurry onto the permeable separator layer.

A preparation method of a cathode material for a secondary battery is provided. First, a lithium metal phosphate material and a first conductive carbon are provided. The lithium metal phosphate material is made of a plurality of secondary particles. Each of the secondary particles is formed by the aggregation of a plurality of primary particles. An interparticle space is formed between the plurality of primary particles. Next, the lithium metal phosphate material and the first conductive carbon are mixed by a mechanical method, and a composite material is prepared. The first conductive carbon is uniformly arranged in the interparticle space. After that, a second conductive carbon, a binder and a solvent are provided. Finally, the composite material, the second conductive carbon, the binder and the solvent are mixed, and a cathode material for preparing a positive plate is prepared.