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                    electrical:severe_battery_use [2020/06/10 17:35] frater_secessus [limiting the damage]                  | 
                
                    electrical:severe_battery_use [2024/03/31 01:42] (current) frater_secessus [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//. | 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//. | 
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| This article is about the intentional and chronic depletion of lead-acid banks below the 50% mark, **followed by vigorous recharging**.  This might be desirable when: | 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: | 
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|   * reducing the weight impact of lead banks |   * reducing the weight impact of lead banks | 
|   * one wants to make use of old/damaged batteries whose capacity has declined |   * one wants to make use of old/damaged/unsuited batteries until replacements can be sourced | 
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| ===== how low can we go? ===== | ===== how low can we go? ===== | 
| ===== limiting the damage ===== | ===== limiting the damage ===== | 
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| Deep cycling generally extends the amount of time for a battery to complete Absorption.   |   | 
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|   * 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]].   |   * 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]]. | 
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| ===== increasing effective Absorption duration =====  |  | 
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| While you may not be able to increase the //actual// Absorption duration,((as when the controller setpoint is maxxed out)) you can achieve a similar effect with one or more of these techniques:   |  | 
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|   * if duration setpoint is maxxed then set Vfloat == Vabs.  Absorption duration will effectively be "until the sun goes down".    |  | 
|   * charge at a lower current (charging minimum).  While [[opinion:frater_secessus:charging_faster|overall charging will take about the same amount of time]], Bulk's share of that time will increase and [[electrical:12v:charging#absorption|Absorption will take somewhat less time]].  |  | 
|   * charge at a higher voltage (Vabs), this will decrease Absorption duration.  Keep a close watch on water levels for flooded batts, and also mind the max allowable voltage for AGM/Gel.  |  | 
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