Philips Xenium X520 can us standard AAA batteries as a supplementary source of power. That's not to say that Philips; Xenium has bad power on it's regular battery, quite the contrary, the phone can take up to 8 hours of talk time and up to a month of standby time. Some of the specs for this phone are:
a 2 megapixel camera, stereo Bluetooth (A2DP) support, FM radio with RDS, music player and a microSD memory card slot.

via: Just Another Mobile Phone Blog: Philips Xenium X520 is running on normal batteries

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