Premature capacity loss (PCL) of the positive lead/acid battery plate: a new concept to describe the phenomenon

摘要: Abstract When the lead—antimony grids in lead/acid batteries were substituted by lead—calcium ones, battery cycle life was dramatically shortened. This phenomenon called first ‘antimony-free effect’ and later ‘premature capacity loss’ (PCL), ‘early decline’ or ‘relaxable insufficient mass utilization’ (RIMU). PCL is encouraged followingconditions: (i) lack of certain alloying additives as antimonym tin positive grid; (ii) high utilization coefficient active mass; (iii) low density; (iv) no stack pressure on plates cells, (v) limiting role H2SO4 Discharge (PAM) proceeds through two successive reactions: For reaction to proceed, equivalent amounts H+ ions from bulk electrolyte electrons plate grid should reach PAM. It has been established that due impeded trasport when passing corrosion layer (CL) A survey concepts various authors for reasons causing distinguished. The one assumes changes PAM during cycling which result following phenomema: impaired contact between PbO2 crystals structure (Kugelhaufen model); intrinsic electrochemical activity (hydrogen-loss model), α/β-PbO2 ratio. second concept electrical properties are reason effect. latter to: formation a PbSO4 barrier layer, α-PbO semiconductor layer. present paper suggests new approach seems unite all above concepts. CL viewed gel/crystals systems. Their particles agglomerates composed α- β-PbO2 crystal zones equilibrium with amorphous gel zones. built up hydrated linear polymer chains along move Crystal have electron conductivity. conductivity determined To asses effect conditions this tubular powder electrode used. surface hydrated. Hence will be those whose surfaces electronic another CL. cycles measure at CL/PAM interface. After 15 restored its depends density additive alloy, solution critical found exist below restoration possible. On volume pulsates, decreasing Gel play ‘hinges’ skeleton making it elastic. active-mass given region outer sublayer falls value, excluded current generation process may occur. antimony lowers value thus prolongs plate. Antimony get into improving appearance explained impact dopants ratio gel/crystal