Your options are limited if you want a newer phone with a removable battery. The LG V20 is a match, but it's spendy. Carriers are asking $700-800, and the unlocked version on Amazon is not much cheaper. However, B&H has the US unlocked phone on discount today. You'll pay just $499.99, but the price goes back up tomorrow.
This version of the V20 is similar to what you can get from carriers with a Snapdragon 820 SoC, 4GB of RAM, 64GB of storage, and a 3200mAh removable battery. There's also the 5.7-inch 1440p LCD and secondary ticker screen on the front. Unlike the carrier versions, this phone is unlocked and supports both GSM and CDMA networks. It's also got a good number of LTE bands.
The same phone (the US996) on Amazon is currently listed at $659.99, and that's down from the $800 retail price. B&H's much better sale will only be live for the next 12 hours as of this posting—that's midnight on the East Coast.