Just chipping in on this as I have just replaced my 12V battery on a 2010 RX450h ... the original battery (dated April 2010 so probably with the car from new) was a D23 wet lead acid battery, a Panasonic battery with Toyota stamped on it, pretty bog standard, not deep cycle. The ones identified above by GSLV6 are too big to sit on the undertray so mayby there are some suble changes in the battery area between 2010 and 2014. I went for a slightly larger size than the D23 and purchased a Bosch S4 Car Battery 005 for £87 from ECP. It fits like a glove in the battery undertray and gives some additional capacity plus a 4 year warranty. Easy enough to fit.