Discharging batteries is entirely a function of your particular application. However, below is list of helpful items:
  1. Shallow discharges will result in a longer battery life.
  2. 50% (or less) discharges are recommended.
  3. 80% discharge is the maximum safe discharge.
  4. Do not fully discharge flooded batteries (80% or more). This will damage (or kill) the battery.
  5. Many experts recommend operating batteries only between the 50% to 85% of full charge range. A periodic equalization charge is a must when using this practice.
  6. Do not leave batteries deeply discharged for any length of time.
  7. lead acid batteries do not develop a memory and need not be fully discharged before recharging.
  8. Batteries should be charged after each period of use.
  9. Batteries that charge up but cannot support a load are most likely bad and should be tested. Refer to the Testing section for proper procedure.

% Discharged
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80
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20
0
0
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% Charged