Positive electrode collector for lead acid storage battery and method for producing the same
A positive electrode current collector for lead-acid batteries contains a current collector substrate of titanium or a titanium alloy, a coating of titanium oxide formed on the surface of the current collector substrate, and a conductive ceramic layer formed on the surface of the coating, and the thickness of the coating is 0.09 μm or thinner.
1. A production method of a positive electrode current collector for lead-acid batteries, comprising:
annealing a current collector substrate made of titanium or titanium alloy in vacuum or inert atmosphere such that a half width of a peak with a maximum intensity in an XRD pattern of the titanium or titanium alloy becomes 0.38° or lower, wherein titanium in the current collector substrate is not oxidized during annealing,
applying a coating solution including SnO 2 on a surface of the current collector substrate, and
firing the current collector substrate to form a titanium oxide coating on the surface of the current collector substrate and a conductive ceramic layer of SnO 2 on the titanium oxide coating, wherein the titanium oxide coating exists such that a thickness of the titanium oxide coating is 0.08 μm or less.
2. A production method of a positive electrode current collector for lead-acid batteries, comprising:
annealing a current collector substrate made of titanium or titanium alloy in vacuum or inert atmosphere such that when four peaks are selected in the order of highest intensities in the XRD pattern of the titanium or the titanium alloy, the step of the annealing makes the total value of intensities of the four peaks be 85% or higher in the total value of the intensities of all peaks, wherein titanium in the current collector substrate is not oxidized during annealing,
applying a coating solution including SnO 2 on a surface of the current collector substrate, and
firing the current collector substrate to form a titanium oxide coating on the surface of the current collector substrate and a conductive ceramic layer of SnO 2 on the titanium oxide coating, wherein the titanium oxide coating exists such that a thickness of the titanium oxide coating is 0.08 μm or less.
3. A production method of a positive electrode current collector for lead-acid batteries according to claim 1 , wherein a thickness of the titanium coating is 0.07 μm or less and more than 0.03 μm.
4. A production method of a positive electrode current collector for lead-acid batteries according to claim 2 , wherein a thickness of the titanium coating is 0.07μm or less and more than 0.03 μm.