Techniques Of Preparing Nickel-plated Steel Strip In High-current And Surface Quality Control For Battery Shell

pre-electroless nickel plating batteries strip is the main building material of the battery case, the battery safety, energy storage and other properties play an important role.Pre-nickel-plated steel corrosion resistance not only to meet the requirements, but also to meet the pressing requirements of the production process of the battery case. To solve the pores appear in the large current electroplating process, burrs, Alice and other issues, this paper at high speed circulating bath conditions, using high current steel plating,nickel-plated steel and then heat treated, flat, get different nickel-plated steel sample, and its performance testing.In this thesis, the following:(1) By using the base material of the punching cold rolling carbon structural steel with the method of high-speed loop bath, using nickel plating under the condition of high current, dark nickel, semi-bright nickel, bright nickel nickel plating combining multiple The method of cold-rolled carbon steel strip electrodeposition. use XRD, SEM and other testing methods for different processes to obtain pre-plated nickel batteries strip microstructure characterization. Studies have shown that the use of high-speed loop plating method, under the condition of high current nickel strip surface a variety of pre-nickel plating combination looks more smooth, more uniform grain size; using Tafel extrapolation curve, AC impedance, neutral salt spray test and other test methods for corrosion resistance of different samples can be tested. Studies have shown that the use of high-speed loop plating method under the conditions of a variety of high-current pre-plated nickel strip corrosion potential nickel process combining the most positive for-4.08V; mass transfer resistance reached a maximum 1284Ωcm2, corrosion resistance better.(2) in nitrogen atmosphere for nickel-plated steel of different heat treatment temperature, the use of XRD, SEM and other testing methods for different heat treatment temperature to obtain pre-plated nickel batteries strip microstructure characterization.Studies have shown that heat treatment after plating(111),(200) has a preferredorientation, 500 ℃ heat treatment recrystallization crystal nucleation, the formation of new grain structure, the nickel plating layer by a high-energy state to a more stable low-energy state; neutral salt spray test, Tafel extrapolation curve, AC impedance method to test different methods for corrosion resistance of the heat treatment temperature of the sample can be tested. Studies have shown that the corrosion potential Tafel curve 500 ℃heat-treated sample was most positive for-3.03 V, the corrosion current is minimized while the mass transfer resistance reached a maximum 2326Ωcm2, resistance to salt spray corrosion longest. The mechanical properties of different samples tested. Research shows that the pre-heat treatment can reduce the hardness of nickel-plated steel, heat treated at500 ℃, the yield ratio of 0.793, an elongation of 39.8%, the minimum roughness; glow discharge apparatus for pre-plating and nickel-plated steel diffusion layer iron and nickel content of the correspondence between the depth of characterization, research shows that the most iron-nickel diffusion layer uniformity of diffusion heat treatment at 500 ℃.(3) to 500 ℃ heat-treated nickel-plated steel strip leveling process. Studies have shown that the formation process enables the pre-nickel-plated steel smoother surface morphology, grain uniformity, more excellent corrosion resistance, while the pre-formation process can enhance the mechanical properties of nickel-plated steel,reducing roughness.In summary, the use of high-speed loop bath at high current plating technology combined with a variety of nickel-plated steel prepared after 500 ℃ heat treatment,smoothing treatment, has good mechanical properties, corrosion resistance, to meet production storage performance and safety needs of the potential of the battery case.