====== Intentionally severe battery use ======

Lead-acid chemistries prefer light cycling and full recharge between those cycles.  Lead-acid batteries are traditional cycled to [[electrical:depth_of_discharge|50% depth of discharge]] because it offers a balance between duty life (years between failure) and bank size.(("dead lead"))  Pulling the bank below 50% DoD in emergnecies will not automatically cause damage //assuming a full charge is accomplished ASAP//.

This article is about the intentional severe use of lead-acid banks by running them below the 50% mark, **followed by vigorous recharging** at maximal voltage.((the high end of the acceptable Absorption range.  Maybe even EQ)).  Perhaps [[electrical:12v:eternal_absorption|forgoing Float altogether]].  This might be desirable when:

  * reducing the weight impact of lead banks
  * one wants to make use of old/damaged/unsuited batteries until replacements can be sourced

===== how low can we go? =====

For folks willing to trade battery longevity for some amount of increased capacity, common low-end targets for [[electrical:12v:lvd|low voltage disconnect]] are:

  * 60% DoD / 40% SoC, ~12.0 rested volts
  * 75% DoD / 25% SoC, ~11.7 rested volts
  * 80% DoD / 20% SoC, ~11.6 rested volts



===== limiting the damage =====


  * get power back into the battery ASAP after deep discharge;  drive for [[electrical:12v:alternator|alternator charging]] or run a [[electrical:generator|generator]] to get bulk stage going.  Solar alone //might// be sufficient but it might require meaningful [[electrical:solar:overpaneling|overpaneling]].  
  * fully charge lead-chemistry batteries as often as possible.  This may require [[electrical:12v:eternal_absorption|special measures to finishing Absorption]].