Cellink is a South Korean manufacturer of high-quality battery packs and power banks. Cellink makes the BlackVue battery packs, among other products, but these are also marketed under their own label. Cellink battery packs are useful for connecting a dashcam without interfering with the car's electrical circuit.
Cellink makes LiFePO (lithium iron phosphate) battery packs that are very handy for powering your dashcam while you are parking. Cellink also offers extension packs to increase the battery's capacity so you never run out of power again.