Japan's semi-solid-state power banks promise 2,000 cycles and fire resistance — from $50

Tama Denshi Kogyo, a Kawasaki-based accessory maker founded in 1976, has launched six semi-solid-state power banks in Japan today. The company claims reduced fire risk thanks to a flame-retardant gel electrolyte replacing the conventional liquid one.

The lineup includes three capacities, each available in black and white. The 10,000 mAh TLP158UC delivers up to 45 W over USB-C and costs 7,980 yen (~$50). The 15,000 mAh TLP159UC and 20,000 mAh TLP160UC both support up to 67 W, priced at 10,800 yen (~$68) and 12,800 yen (~$80) respectively. All models feature a captive USB-C cable, a USB-C port, a USB-A port, a charge-level readout, and over-current and over-voltage protection.

However, total output drops to 30 W when more than one connection is drawing power. The 67 W figure that makes the larger two models suitable for laptop charging only applies when nothing else is plugged in. Charging three devices simultaneously, as the company suggests, means sharing just 30 W among them.

The battery uses a semi-solid-state design with a gel electrolyte instead of liquid. Tamadenco claims roughly 2,000 charge cycles and stable output in both heat and cold. It is worth noting that semi-solid-state cells still contain some liquid — Japan's target for practical all-solid-state batteries is around 2030.

The timing of the launch is not accidental. In March, Elecom shipped a comparable 10,000 mAh unit for 8,480 yen, and the industry is clearly shifting toward safer battery chemistries. Tama Denshi Kogyo, despite being a lesser-known brand outside Japan, is positioning itself early in this transition.