Powder comprising particles comprising a matrix material and silicon-based domains dispersed in this matrix material, whereby the matrix material is carbon or a material that can be thermally decomposed to carbon, whereby either part of the silicon-based domains are present in the form of agglomerates of silicon-based domains whereby at least 98% of these agglomerates have a maximum size of 3 μm or less, or the silicon-based domains are not at all agglomerated into agglomerates.

A permeable composite material for making an electrode for an electrochemical cell, the composite material comprising: a support defining pores; and alkali metal deposited on the support within a plurality of said pores. An electrode comprising the composite material is also described, as are methods of making the material and cells and assemblies comprising the electrode.

A permeable composite material for making an electrode for an electrochemical cell, the composite material comprising: a support defining pores; and alkali metal deposited on the support within a plurality of said pores. An electrode comprising the composite material is also described, as are methods of making the material and cells and assemblies comprising the electrode.

A negative electrode active material includes a silicon-containing alloy having a composition represented by: Si.sub.xSn.sub.yM.sub.zA.sub.a (A is unavoidable impurities, M is one or more transition metal elements, x, y, z, and a represent values of percent by mass, and 0<x<100, 0<y<100, 0<z<100, and 0≦a <0.5 and x+y+z+a=100). The silicon-containing alloy has a lattice image subjected to Fourier transform processing to obtain a diffraction pattern and a size determined as an average value of maximum five major axis diameters of regions having a periodic array from a Fourier image obtained by subjecting a diffraction ring portion present in a width of from 0.7 to 1.0 when a distance between Si regular tetrahedrons is 1.0 in this diffraction pattern to inverse Fourier transform is 10 nm or less.

A method for preparing an electrode for use in lithium batteries and the resulting electrodes are described The method comprises coating a slurry of silicon, sulfur doped graphene and polyacrylonitrile on a current collector followed by sluggish heat treatment.

This disclosure relates to an SO.sub.2-based electrolyte for a rechargeable battery cell containing at least one conducting salt of the Formula (I) ##STR00001##
wherein M is a metal selected from the group consisting of alkali metals, alkaline earth metals, metals of group 12 of the periodic table of the elements and aluminum; x is an integer from 1 to 3; the substituents R, R.sup.2, R.sup.3 and R.sup.4 are each independently selected from the group consisting of C.sub.1-C.sub.10 alkyl, C.sub.2-C.sub.1 alkenyl, C.sub.2-C.sub.1 alkynyl, C.sub.3-C.sub.10 cycloalkyl, C.sub.6-C.sub.14 aryl, and C.sub.5-C.sub.14 heteroaryl; and Z is aluminum or boron.

This disclosure relates to an SO.sub.2-based electrolyte for a rechargeable battery cell containing at least one conducting salt of the Formula (I) ##STR00001##
wherein M is a metal selected from the group consisting of alkali metals, alkaline earth metals, metals of group 12 of the periodic table of the elements and aluminum; x is an integer from 1 to 3; the substituents R, R.sup.2, R.sup.3 and R.sup.4 are each independently selected from the group consisting of C.sub.1-C.sub.10 alkyl, C.sub.2-C.sub.1 alkenyl, C.sub.2-C.sub.1 alkynyl, C.sub.3-C.sub.10 cycloalkyl, C.sub.6-C.sub.14 aryl, and C.sub.5-C.sub.14 heteroaryl; and Z is aluminum or boron.

Systems and methods for water based phenolic binders for silicon-dominant anodes may include an electrode coating layer on a current collector, where the electrode coating layer is formed from silicon and a pyrolyzed water-based phenolic binder. The water-based phenolic binder may include phenolic/resol type polymers crosslinked with poly(methyl vinyl ether-alt-maleic anhydride), poly(methyl vinyl ether-alt-maleic acid), and/or Poly(acrylamide-co-diallyldimethylammonium chloride) (PDADAM). The electrode coating layer may further include conductive additives. The current collector may comprise one or more of a copper, tungsten, stainless steel, and nickel foil in electrical contact with the electrode coating layer. The electrode coating layer may include more than 70% silicon. The electrode may be in electrical and physical contact with an electrolyte, where the electrolyte includes a liquid, solid, or gel. The battery electrode may be in a lithium ion battery.

Systems and methods for water based phenolic binders for silicon-dominant anodes may include an electrode coating layer on a current collector, where the electrode coating layer is formed from silicon and a pyrolyzed water-based phenolic binder. The water-based phenolic binder may include phenolic/resol type polymers crosslinked with poly(methyl vinyl ether-alt-maleic anhydride), poly(methyl vinyl ether-alt-maleic acid), and/or Poly(acrylamide-co-diallyldimethylammonium chloride) (PDADAM). The electrode coating layer may further include conductive additives. The current collector may comprise one or more of a copper, tungsten, stainless steel, and nickel foil in electrical contact with the electrode coating layer. The electrode coating layer may include more than 70% silicon. The electrode may be in electrical and physical contact with an electrolyte, where the electrolyte includes a liquid, solid, or gel. The battery electrode may be in a lithium ion battery.

This invention relates to particulate electroactive materials consisting of a plurality of composite particles, wherein the composite particles comprise a plurality of silicon nanoparticles dispersed within a conductive carbon matrix. The particulate material comprises 40 to 65 wt % silicon, at least 6 wt % and less than 20% oxygen, and has a weight ratio of the total amount of oxygen and nitrogen to silicon in the range of from 0.1 to 0.45 and a weight ratio of carbon to silicon in the range of from 0.1 to 1. The particulate electroactive materials are useful as an active component of an anode in a metal ion battery.