Anker PowerCore Battery Pack

Anker PowerCore Battery Pack charges a phone four to five times over with 20,800 mAh capacity, delivering 18W power faster than the average portable charger by 35%. It's compact enough for a jacket pocket and has been through more airport security scans than most passports. Anker's 18-month warranty covers defects, and independent tests show it retains 80% capacity after 500 cycles — outperforming #5 for longevity. At $27, it's 40% cheaper than the runner-up with comparable specs.