Maxoak Direct via Amazon offers its Maxoak 50,000mAh Power Bank Laptop Charger for $135.99. Coupon code "RM3ALPPG" cuts it to $99.27. Plus, Prime members receive free shipping. It ships with 14 laptop connectors and can charge most laptops as well as cell phones. Deal ends August 31.
Note that it cannot charge Apple laptops. Otherwise, check the information on the product page to know if its compatible with your laptop.