You don't mention your budget, but understandably more expensive and larger PHEVs tend to have the longest battery-only range. The Mercedes-Benz C300e offers a range of 68 miles and the BMW X1 xDrive30e offers 55 miles, while slightly less expensive offerings like the BMW 225e Active Tourer and the Toyota RAV4 can manage close to 50 miles on electric-only. It's also worth remembering that these figures are based on the WLTP testing program, so your actual results in the real world will vary according to weather, driving style, traffic and so on.