Sanwa's new power bank tackles forgotten cables and battery safety concerns

A power bank is a useful thing to carry around, provided you also remember packing the charging cable. Sanwa Supply's new 700-BTL064BK addresses that small but remarkably persistent problem with a retractable USB-C cable built directly into its housing.

The cable extends approximately 70cm and retracts when not in use, avoiding the usual tangle of wires at the bottom of a backpack. It works in both directions, allowing users to charge their smartphone or recharge the power bank itself without carrying another cable.

However, the retracting cable isn't the only interesting feature. Sanwa has equipped the 10,000mAh device with a semi-solid lithium-ion battery rather than a conventional liquid-electrolyte design. According to the manufacturer, this construction reduces the likelihood of overheating and swelling.

The power bank also includes temperature monitoring and protection against overcurrent, overcharging, excessive discharge and short circuits. These safety advantages remain manufacturer claims rather than independently verified improvements.

However, the retracting cable isn't the only interesting feature. Sanwa has equipped the 10,000mAh device with a semi-solid lithium-ion battery rather than a conventional liquid-electrolyte design. According to the manufacturer, this construction reduces the likelihood of overheating and swelling. The power bank also includes temperature monitoring and protection against overcurrent, overcharging, excessive discharge and short circuits. These safety advantages remain manufacturer claims rather than independently verified improvements.

Charging specifications include up to 30W USB Power Delivery with PPS support. A separate USB-C port allows two devices to charge simultaneously, although maximum output is reduced when both connections are in use. The power bank weighs approximately 225g and measures 137 × 74 × 15mm. A digital display shows remaining battery capacity in 1% increments, while its 37Wh capacity falls below the commonly applied 100Wh airline carry-on limit. Airline-specific rules still apply.

Sanwa has priced the 700-BTL064BK at ¥6,980 (approximately $45), with Japanese availability through Rakuten or Amazon JP.

It won't eliminate every charging inconvenience, but having the cable permanently attached removes at least one opportunity to forget something important.