- #1
yahastu
- 79
- 7
A typical off grid solar system looks like this:
PV Array -> MPPT controller -> Battery bank -> 240v AC inverter -> loads
Suppose that the system is currently float charging:
"Float charging, also called trickle charging, consists of charging the battery at the same rate that it is discharging. This just keeps the batteries fully charged."
I am curious what is going on inside the batteries when they are float charging like this. Does the current basically just skip over the battery terminals from the MPPT controller directly to the 240 VAC inverter in this case, rather than being converted into chemical energy inbetween?
If so, does this mean that the battery size/chemistry in no way impedes the flow of current - meaning that while float charging, even a really slow charging battery would not present a bottleneck, because the current isn't really going through the battery anyway?
EDIT: The reason I ask is because I want to add a non-critical high amp loads panel that is controlled by a current relay to the PV generation. This way, I can plug non-essential high amperage loads (eg, EV charger) into a special breaker box which is only activated with power when the PV generation capacity supports it directly, without putting strain on the battery system.
I know that I could do this using an AC Coupled system, but I prefer to avoid AC coupled systems if possible because most of them are designed for grid based systems and there can be compatibility issues. So, I'm wondering if this would just work in a regular off grid design.
PV Array -> MPPT controller -> Battery bank -> 240v AC inverter -> loads
Suppose that the system is currently float charging:
"Float charging, also called trickle charging, consists of charging the battery at the same rate that it is discharging. This just keeps the batteries fully charged."
I am curious what is going on inside the batteries when they are float charging like this. Does the current basically just skip over the battery terminals from the MPPT controller directly to the 240 VAC inverter in this case, rather than being converted into chemical energy inbetween?
If so, does this mean that the battery size/chemistry in no way impedes the flow of current - meaning that while float charging, even a really slow charging battery would not present a bottleneck, because the current isn't really going through the battery anyway?
EDIT: The reason I ask is because I want to add a non-critical high amp loads panel that is controlled by a current relay to the PV generation. This way, I can plug non-essential high amperage loads (eg, EV charger) into a special breaker box which is only activated with power when the PV generation capacity supports it directly, without putting strain on the battery system.
I know that I could do this using an AC Coupled system, but I prefer to avoid AC coupled systems if possible because most of them are designed for grid based systems and there can be compatibility issues. So, I'm wondering if this would just work in a regular off grid design.
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