遇到了这个问题，网上找了好久，亲测有效，根据体验，待机时间提长了不止一点点：
The problem is the macOS continues to check for updates (including email, software, news, etc.) while your MacBook Pro is asleep. This means it's very quick to get up and running, but it also means your battery goes down.
To fix it, you can tell you MacBook Pro to disconnect from the Internet while it's asleep.
To do this, you need to set the tcpkeepalive setting to 0.
Open up Terminal and type:
sudo pmset -b tcpkeepalive 0
After you enter your password for sudo it gives you a warning saying some features may not work properly. This is fine, it simply disables Internet access during sleep.
You can check it is set correctly by running:
pmset -g
Which should show "tcpkeepalive 0"
And you can, of course, reverse it at any time by running:
sudo pmset -b tcpkeepalive 1
Simple!
Note: You can also force your Mac not to connect to the Internet when it's asleep even when connected to a power supply, if you like: sudo pmset -a tcpkeepalive 0. (Personally I don't mind as long as it's not using my battery, so -b is fine for me.)
Also note: The results from pmset -g will vary depending on if your MacBook Pro is connected to power or not when you run the command. It will reflect the current tcpkeepalive setting, depending on its current power situation.
转自 StackExchange： https://apple.stackexchange.com/questions/253776/macbook-pro-13-with-retina-display-consumes-10-battery-overnight-with-the-lid-c
这样做过之后一个很烦的事情就是每次display off的时候都会断网，这是因为系统默认是display off的时候就变成sleep模式，作如下设置：
Preferences -> Energy Saver -> tick Prevent computer from sleeping automatically when the display is off
