Here is a summary of the main PC parts found in Akihabara from March 30 to April 5, 2015.
TEC "TACMB-18K"
21,800 yen (including tax): Techno House Toei
In addition to 2 USB ports for power supply, this mobile battery has an AC output terminal that can output up to 85W.
The AC output terminal can be used like a regular outlet, and an adapter can be connected to charge a notebook PC or use a small household appliance.
The main specifications are as follows: main unit size is186(W) x 129 (D) x 28 (H) mm, weight is 610 g. Battery capacity is 18,000 mAh; input is 20 VDC/2 A. Output is USB port: 5 V/2.1 A, AC output terminal: 120 V 60 Hz (85 W maximum).