Aukey loves to offer deals on its products. Right now on Amazon, you can get the Quick Charge 3.0 Car Charger for $9 if you redeem the "Buy 1, get 55% off" promotion right underneath the price. (Mobile users may need to scroll further down the page to see the promotion.)
This charger can charge two "compatible devices" up to four times faster than normal chargers, according to Aukey, as it supports Qualcomm's Quick Charge 3.0 technology. (Hence the product's name.) The charger is also loaded with safeguards to prevent excessive current from overloading your devices. That should just be a standard part of any charging device, mind you--especially car chargers.