Both sides previous revision
Previous revision
Next revision
|
Previous revision
Next revision
Both sides next revision
|
electrical:depth_of_discharge [2023/08/17 17:28] frater_secessus [Depth of discharge / State of Charge] |
electrical:depth_of_discharge [2023/08/17 20:43] frater_secessus [Depth of discharge / State of Charge] |
===== Depth of discharge / State of Charge ===== | ===== Depth of discharge / State of Charge ===== |
| |
{{ http://popupbackpacker.com/wp-content/uploads/2013/12/State-of-Charge-Chart-Trojan.jpg?200|}}//Depth-of-discharge (DoD or DOD)// refers to how low a deep cycle battery is taken between [[electrical:12v:charging|full charges]]. DoD is the inverse of //State of Charge (SoC)//. Example: a battery at 30% DoD is at 70% SoC. | {{ http://popupbackpacker.com/wp-content/uploads/2013/12/State-of-Charge-Chart-Trojan.jpg?200|}}//Depth-of-discharge (DoD or DOD)// refers to how low a deep cycle battery is taken between [[electrical:12v:charging|full charges]]. Specifically, what percentage of the rated capacity remains at a given point? Example: For solar powered systems the greatest DoD (and therefore lowest SoC) will be in early morning just before the panels start creating power again. |
| |
For solar powered systems the greatest DoD (and therefore lowest SoC) will be in early morning just before the panels start creating power again. | DoD is the inverse of //State of Charge (SoC)//. Example: a battery at 30% DoD is at 70% SoC. |
| |
DoD has a **significant impact on longevity of lead deep cycle batteries**.((and, to a lesser degree, lithium batteries)) For this reason [[electrical:inverter|Inverters]] and other high-load devices may have a [[electrical:12v:lvd|low voltage cutoff]]. | DoD has a **significant impact on longevity of lead deep cycle batteries**.((and, to a lesser degree, lithium batteries)) For this reason [[electrical:inverter|Inverters]] and other high-load devices may have a [[electrical:12v:lvd|low voltage cutoff]] to prevent going below a given SoC, typically 50%. |
| |
Note: This information is primarily relevant to lead-chemistry batteries. Lithium batteries have [[:#lithium_soc|different DoD capabilities and lifecycles]]. | Note: This information (including the chart to the right) is primarily relevant to lead-chemistry batteries. Lithium batteries have [[#lithium_soc|different DoD capabilities and lifecycles]]. |
===== effect of DoD on battery life ===== | ===== effect of DoD on battery life ===== |
| |
This section [[electrical:12v:psoc|has moved]]. | This section [[electrical:12v:psoc|has moved]]. |
| |
| ===== lithium SoC ===== |
| |
| Lithium chemistries have very flat voltage curves, making it notoriously difficult to gauge SoC by voltage. In this case [[electrical:12v:battery_monitor|a shunted battery monitor]] is used to count amps as they go in/out. If the Li battery has connectivity you may be able to read SoC from the internal BMS. |