초록 ▼

Recrystallized lead and lead alloy positive electrodes for lead acid batteries having an increased percentage of special grain boundaries in the microstructure, preferably to at least 50%, which have been provided by a process comprising steps of working or straining the lead or lead alloy, and subs

Recrystallized lead and lead alloy positive electrodes for lead acid batteries having an increased percentage of special grain boundaries in the microstructure, preferably to at least 50%, which have been provided by a process comprising steps of working or straining the lead or lead alloy, and subsequently annealing the lead or lead alloy. Either a single cycle of working and annealing can be provided, or a plurality of such cycles can be provided. The amount of cold work or strain, the recrystallization time and temperature, and the number of repetitions of such steps are selected to ensure that a substantial increase in the population of special grain boundaries is provided in the microstructure, to improve resistance to creep, intergranular corrosion and intergranular cracking of the electrodes during battery service, and result in extended battery life and the opportunity to reduce the size and weight of the battery.

대표청구항 ▼

Recrystallized lead and lead alloy positive electrodes for lead acid batteries having an increased percentage of special grain boundaries in the microstructure, preferably to at least 50%, which have been provided by a process comprising steps of working or straining the lead or lead alloy, and subs

Recrystallized lead and lead alloy positive electrodes for lead acid batteries having an increased percentage of special grain boundaries in the microstructure, preferably to at least 50%, which have been provided by a process comprising steps of working or straining the lead or lead alloy, and subsequently annealing the lead or lead alloy. Either a single cycle of working and annealing can be provided, or a plurality of such cycles can be provided. The amount of cold work or strain, the recrystallization time and temperature, and the number of repetitions of such steps are selected to ensure that a substantial increase in the population of special grain boundaries is provided in the microstructure, to improve resistance to creep, intergranular corrosion and intergranular cracking of the electrodes during battery service, and result in extended battery life and the opportunity to reduce the size and weight of the battery. of at least one oil-soluble amphiphile which comprises nitrogen- or oxygen-containing groups substituted by alkyl, alkenyl, hydroxyalkyl or aromatic radicals, and B) 5-90% by weight of at least one copolymer which contains B1) from 0.5 to 15 mol % of structural units which are derived from olefinically unsaturated compounds which have at least one free hydroxyl group, and B2) from 85 to 99.5 mol % of structural units which are derived from ethylene, and, if required, B3) from 0 to 20 mol % of further structural units selected from the group consisting of (meth)acrylic acid, (meth)acrylates, vinyl esters, vinyl ethers and alkenes, and the copolymer has an average molar mass Mw of from 500 to 100,000 g/mol and an OH number of from 5 to 500 mg KOH/g.