This object represents the status of the battery.
unknown - Battery status is unknown.
normal - Battery is operating normally and is in
standby mode ready to takeover if
input AC power supply fails.
overloaded - Battery is overloaded when more current than
the specified rating is drawn.
low - Battery has low voltage when the output voltage
is less than 11 Volts.
acfail - External AC power supply has failed.
replace - Battery must be replaced when it does not
recharge fully and is at less than 70% capacity.
missing - One or more batteries in the battery string
is missing. The battery string has normally
4 batteries.