I see such messages being repeated in journal all the time:


[ 1106.139531] upowerd[1669]: The estimated charge rate is 0.000000W, which is
not realistic
[ 1106.141620] upowerd[1669]: value "-nan" of type 'gdouble' is invalid or out
of range for property 'percentage' of type 'gdouble'
[ 1111.227937] upowerd[1669]: The estimated charge rate is 0.000000W, which is
not realistic
[ 1111.229783] upowerd[1669]: value "-nan" of type 'gdouble' is invalid or out
of range for property 'percentage' of type 'gdouble'
[ 1116.320043] upowerd[1669]: The estimated charge rate is 0.000000W, which is
not realistic
[ 1116.321943] upowerd[1669]: value "-nan" of type 'gdouble' is invalid or out
of range for property 'percentage' of type 'gdouble'
[ 1121.411956] upowerd[1669]: The estimated charge rate is 0.000000W, which is
not realistic
[ 1121.414238] upowerd[1669]: value "-nan" of type 'gdouble' is invalid or out
of range for property 'percentage' of type 'gdouble'
[ 1126.504980] upowerd[1669]: The estimated charge rate is 0.000000W, which is
not realistic
[ 1126.506916] upowerd[1669]: value "-nan" of type 'gdouble' is invalid or out
of range for property 'percentage' of type 'gdouble'


This makes it very difficult to watch for other events in the log.

*FWIW this laptop's battery has been dysfunctional for many years but this has
never resulted in such journal flood.