Abstract: An electrically insulating gas composition comprises C3F7CN, in an amount between 22% and 70% by volume and one or more inert gas selected from the list consisting of nitrogen, carbon dioxide (CO2), air and argon.

Abstract: A battery or fuel cell module comprising a plurality of battery cells or fuel cells and metal foam bus bars that electrically connect together at least some of the battery cells or fuel cells is described. The battery or fuel cell module may further include a cooling system arranged to provide a flow of cooling fluid through the metal foam bus bars to remove heat from the bus bars. In some examples, the cooling system comprises one or more forced air devices. In other examples, the metal foam bus bars are encased in a fluid-impermeable skin so that the bus bars form fluid-tight pipes with a metal foam interior, and the cooling system is arranged to provide the flow of cooling fluid through the metal foam interior of the fluid-tight pipes.

Abstract: A method of manufacturing a winding assembly for an electrical machine, the method comprising: forming, by three-dimensional, 3D, printing, an electrically insulating body comprising a channel defining a winding path, the channel having an inlet and an outlet; heating the electrically insulating body to a temperature above the melting point of an electrically conducting material; flowing the electrically conducting material through the inlet to the outlet to fill the channel; and cooling the electrically insulating body to solidify the electrically conducting material within the channel, thereby forming said winding assembly.

Abstract: A method of manufacturing a winding assembly for an electrical machine, the method comprising: selecting (S1) a mathematical function defining the spatial separation between adjacent turns of a winding path, the mathematical function dependent on one or more parameters of the electrical machine and/or of the anticipated operating environment of the electrical machine; forming (S2), by three-dimensional, 3D, printing, an electrically insulating body comprising a channel defining the winding path in accordance with said function, the channel having an inlet and an outlet; heating (S3) the electrically insulating body to a temperature above the melting point of an electrically conducting material; flowing (S4) the electrically conducting material through the inlet to the outlet to fill the channel; and cooling the electrically insulating body to solidify the electrically conducting material within the channel, thereby forming said winding assembly.

Abstract: A procedure for repairing a polymer matrix composite component is provided. The procedure includes the steps of: providing a polymer matrix composite component having a site prepared for repair by removal of damaged or defective material; locating an uncured, polymer matrix composite repair patch at the site to re-build the component thereat; and curing the polymer matrix of the repair patch by heating the patch using eddy currents induced by one or more alternating current coils. The repair patch is without metallic additives, such that the repaired polymer matrix composite after the curing step is also without metallic additives in the vicinity of the repair patch.

Abstract: A method of manufacturing a winding assembly for an electrical machine, the method comprising: selecting (S1) a mathematical function defining the spatial separation between adjacent turns of a winding path, the mathematical function dependent on one or more parameters of the electrical machine and/or of the anticipated operating environment of the electrical machine; forming (S2), by three-dimensional, 3D, printing, an electrically insulating body comprising a channel defining the winding path in accordance with said function, the channel having an inlet and an outlet; heating (S3) the electrically insulating body to a temperature above the melting point of an electrically conducting material; flowing (S4) the electrically conducting material through the inlet to the outlet to fill the channel; and cooling the electrically insulating body to solidify the electrically conducting material within the channel, thereby forming said winding assembly.

Abstract: A method of manufacturing a winding assembly for an electrical machine, the method comprising: forming, by three-dimensional, 3D, printing, an electrically insulating body comprising a channel defining a winding path, the channel having an inlet and an outlet; heating the electrically insulating body to a temperature above the melting point of an electrically conducting material; flowing the electrically conducting material through the inlet to the outlet to fill the channel; and cooling the electrically insulating body to solidify the electrically conducting material within the channel, thereby forming said winding assembly.

Abstract: A procedure for repairing a polymer matrix composite component is provided. The procedure includes the steps of: providing a polymer matrix composite component having a site prepared for repair by removal of damaged or defective material; locating an uncured, polymer matrix composite repair patch at the site to re-build the component thereat; and curing the polymer matrix of the repair patch by heating the patch using eddy currents induced by one or more alternating current coils. The repair patch is without metallic additives, such that the repaired polymer matrix composite after the curing step is also without metallic additives in the vicinity of the repair patch.