LG's flagship smartphone, with a unique slide-out battery and detachable I/O module supporting multiple hardware expansion options. Released in April 2016.
This is possibly a processor failure I would try and get a known good battery that is charged and try and turn it on. If it will not turn on with that battery then you are looking at a bad processor. The processor on the LGs due tend to overheat all the way up to the LG V20.