2012 Rx450h 105,300 miles - MPG Averages are dropping!

[aw4golf]

Worried about the remaining life of the high voltage hybird drive battery, it seems to be starting the gas engine more often for a recharge and not giving as many city driving miles when under 25-30 mph.

Have any club members had to replace their RX high voltage drive battery? If so, with what type (new original or lithium, rebuilt, used, 3rd party, or?) and when (miles, years) and total cost (battery, Installation)?

Thanks in advance for responses.