The effects of grid design variables in valve regulated standby batteries

Positive grid corrosion is one of the major causes of lead-acid battery performance failures. This phenomenon occurs slowly under normal conditions, so that any modifications of the grid design should be undertaken only after an extended testing period. It is very desirable to accelerate simulated battery life in order to obtain data on the status of corrosion, to correct problems, and ultimately to improve the battery service life. Tests in the technical literature are discussed where temperature is used to accelerate corrosion and growth. It has been confirmed that corrosion phenomena accelerate as temperature increases and that this increase is, in the case of lead calcium alloys, proportional to the square of the number of test days. Some results of the FIAMM grid testing program are offered for evaluation and discussion. FIAMM has made significant changes to the positive grids used in its Monolite series of valve-regulated lead-acid batteries. The type-S grid has been redesigned by increasing the cross-section areas of several of the horizontal and vertical ribs, which has increased the grid weight.<>