Each battery chemistry delivers its own unique discharge signature. While voltage-based SoC works reasonably well for a lead acid battery that has rested, the flat discharge curve of nickel- and lithium-based batteries renders the voltage method impracticable.
Here is how it works: When the lead acid battery accepts charge, the sulfuric acid gets heavier, causing the specific gravity (SG) to increase. As the SoC decreases through discharge, the sulfuric acid removes itself from the electrolyte and binds to the plate, forming lead sulfate.
The percentage of a battery directly reflects its state of charge (SoC). When we say a battery is at 50%, half of its total capacity is available for use. So, if a battery has a total capacity of 100 amp-hours (Ah), a 50% SoC indicates that 50 amp-hours remain. This relationship is straightforward: the percentage represents the SoC. 2.
The hydrometer offers an alternative to measuring SoC of flooded lead acid batteries. Here is how it works: When the lead acid battery accepts charge, the sulfuric acid gets heavier, causing the specific gravity (SG) to increase.
Determining State of Charge from Voltage: Determination of battery state of charge from loaded or open circuit voltage is notionally possible, but depends on many factors - with major ones being temperature & specific gravity of electrolyte. Here are some curves for various discharge rates.
While voltage-based SoC works reasonably well for a lead acid battery that has rested, the flat discharge curve of nickel- and lithium-based batteries renders the voltage method impracticable. The discharge voltage curves of Li-manganese, Li-phosphate and NMC are very flat, and 80 percent of the stored energy remains in the flat voltage profile.
Okay, like the title suggests, I need a method of calculating self discharge rates of Lead-Acid batteries. Here''s the catch: I varied the electrolyte which the batteries were using, replacing sulphuric acid with hydrochloric acid, another one with …