Some cool battery graphs
I'm checking out the Costco GC2 batteries and Iota 55A converter as well as the new 16-bit a/d for Arduino. Prior to discharging the 208AH GC2 batteries, they were top charged with 16V for about ...
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The 55A Iota IQ4 converter is in boost for 80 minutes. SOC at that point is 87%. At the 65 min mark the battery is at 14.5V and the converter at 14.8V. This triggers a timer within the Iota and it remains in boost mode for an additional 15 min, or to the 80 min mark.
Current slopes downward at 65 min because the Iota output voltage reached the limit of 14.8V. In other words, tapering begins.
In boost, battery voltage rises fairly linearly, until about 50 min into charging. Voltage begins to increase faster an that point. That's due to the increase in battery resistance starting around 75% SOC.
The right side y-axis scale is for current and SOC.
Another interesting point is when converter voltage drops from 14.8V to 14.2V. Battery surface charge and IR drop reduces, causing it to accept about 8A more current. In other words, dropping from 14.8V to 14.2V is not that huge.
Current slopes downward at 65 min because the Iota output voltage reached the limit of 14.8V. In other words, tapering begins.
In boost, battery voltage rises fairly linearly, until about 50 min into charging. Voltage begins to increase faster an that point. That's due to the increase in battery resistance starting around 75% SOC.
The right side y-axis scale is for current and SOC.
Another interesting point is when converter voltage drops from 14.8V to 14.2V. Battery surface charge and IR drop reduces, causing it to accept about 8A more current. In other words, dropping from 14.8V to 14.2V is not that huge.
