What happened

Shares of Chinese electric-vehicle maker NIO (NIO -0.86%) were trading higher on Monday after the company said that it set a new monthly record for deliveries in December. As of 10:45 a.m. EST, NIO's American depositary shares were up about 11.1% from Friday's closing price.

So what

NIO said that it ended 2020 on a high note, with 7,007 vehicles delivered in December, a 121% increase from a year ago and a new monthly record for the company.

That total includes 2,009 of NIO's flagship ES8 SUVs, 2,493 of its midsize ES6 SUVs, and 2,505 of its newest model, the sporty EC6 crossover. 

A blue NIO EC6, a sporty upscale five-passenger crossover SUV with a sloping, coupe-like roofline.

NIO launched its newest model, the EC6, in September. The sporty crossover has quickly become its bestseller. Image source: NIO, Inc.

Of note for auto investors: Over 40% of NIO buyers in December opted for the company's batteries-as-a-service option, which allows buyers to purchase a vehicle without a battery (at a reduced price) with a subscription to NIO's battery-swap service. This option helps make NIO vehicles more affordable upfront, while creating an ongoing revenue stream for the company. 

NIO has over 150 automated battery-swap stations operating in China. The drive-in stations can "recharge" a NIO by swapping in a fresh battery in about 3 minutes, considerably less time than it would take to recharge at a charging station. 

Now what

NIO said that it will reveal its next new model, a sedan, at its annual "NIO Day" event on Saturday. The company said it will also update investors and customers on the status of its self-driving development program and other new technologies at the event.

NIO is expected to report its fourth-quarter and full-year financial results in mid-February.