set xdata time
set format x "%H:%M"
set grid xtics ytics
plot [] "linio_battery1.data" using ($1-1218213330):3 smooth bezier

set term png medium transparent size 1280x1024
set output "linio_battery1_voltage.png"
plot [] "linio_battery1.data" using ($1-1218213330):3 smooth bezier
set output "linio_battery1_charge.png"
plot [] "linio_battery1.data" using ($1-1218213330):2 smooth bezier