Alber Cellcorder CRT-300, Руководство пользователя

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Application Note CC-001
79
Figure 6 reveals how a battery with an electrochemical resistance
problem behaves. Its reduced capacity does not become apparent until
much further into the discharge, like “running out of fuel.” On the other
hand, the metallic resistance problem can be viewed as pinching the fuel
line! In either case, the worse the resistance, the greater the shortfall
between the cell’s
rated and actual capacity.
BATTERY AGING AND INTERNAL RESISTANCE
Internal resistance provides a clue to aging. The aging process of a
battery’s cells is based upon the rates at which their materials and
construction deteriorate under design conditions. For example, the life of
nearly all stationary cells is specified at 77

F, under particular float
charge conditions and discharges of stipulated depth and frequency.
Very slow corrosion of conduction paths, the loosening of active
materials from plates, grid deformation and, in the case of VRLA cells,
dry out of electrolyte are all
natural processes that push a cell to its end
life. This aging process is marked by increasing cell internal resistance
and decreasing capacity. It is generally agreed that below 80% actual
capacity, the cell’s deterioration will accelerate rapidly and replacement
is recommended.
The internal resistance increases slowly but, toward the end of a cell's
life, it accelerates greatly. Its end-life value is normally about 25% or so
above its initial value, but can be as high as 50%.