Abstract: A battery pack with a reduced resistance connection arrangement in which battery cells are arranged in rows in an insulating case and an electrode of each battery cell is coupled to an electrode of another battery cell through a connecting metallic plate. The connecting metallic plate is made of copper and is disposed on a positive electrode of one battery cell and a negative electrode of another battery cell to form a lap joint. Welds are formed in predetermined positions on the connecting metallic plate above the positive and negative electrodes by arc spot welding. The electrodes are formed of nickel-coated steel. The depth h of weld penetration in the weld is greater than the thickness T1 of the connecting metallic plate and smaller than the thickness T1 plus the thickness T2 of one of the electrodes, that is, T1<h?(T1+T2×4/5).

Abstract: An upper plate is arranged on the top surface of a lower vertical plate to form a T-type joint, and a penetration promoter is applied on the surface of the upper plate of the T-type joint. Subsequently, when performing non-consumable electrode arc welding, a penetration width w of a molten pool on the side of the vertical plate after penetrating through the back side of the vertical plate is formed equal to or greater than the vertical plate thickness if a lower vertical plate thickness is the same thickness as an upper plate thickness or thinner than the upper plate thickness, and the penetration width of the molten pool is formed equal to or greater than the upper plate thickness if the lower vertical plate thickness is thicker than the upper plate thickness, thereby forming a penetration shape having a desired welding metal part.

Abstract: In a battery pack in which multiple battery cells are arranged in one or multiple rows in an electrically insulating case and an electrode of each battery cell is coupled to an electrode of another battery cell through a connecting metallic plate, the connecting metallic plate made of copper is disposed on a positive electrode of each battery cell and on a negative electrode of another battery cell to form a lap joint, and a weld is formed in each of one predetermined position on the connecting metallic plate 3 above the positive electrode and another predetermined position on the connecting metallic plate above the negative electrode by applying arc spot welding. The depth h of weld penetration in the weld is greater than the thickness T1 of the connecting metallic plate and smaller than the thickness T1 plus the thickness T2 of the positive electrode or the negative electrode, that is, T1<h?(T1+T2×4/5).

Abstract: The present invention has an object to reduce residual stress in a tensile direction of a weld on the inner side in contact with reactor water of austenitic stainless steel piping, and to change the residual stress into compressive stress, to reduce stress corrosive cracking. The present invention provides a welding process for stainless steel piping of laminating two types of welding wire made of different materials in a groove of austenitic stainless steel piping, including at least one of a first layer penetration welding step of performing a predetermined back bead width on the back side of the groove bottom and a tack welding step, a first lamination welding step of lamination welding of austenitic stainless steel wire from the bottom to the top of the groove, and a second lamination welding step of lamination welding of nickel-base alloy wire to a final layer at the top of the groove.

Abstract: Aluminum or its alloy is subjected to surface treatment wherein the surface is heated and melted by the heat of an electric arc in an atmosphere of a mixture of inert gas and nitrogen gas. By this treatment, a dense layer of aluminum nitride is formed on the surface of aluminum or its alloy so that material of increased wear resistance is obtained.