's lower deliveries in August may be related to a brief production suspension of its F1 plant in late July through early August for upgrades.

Nio (NYSE: NIO) continued to see strong deliveries in August, albeit down slightly from July.

The company delivered 19,329 vehicles in August, up 81.03 percent year-on-year, but down 5.54 percent from July, according to data it released today.

Although the delivery was down from July's record 20,462 vehicles, it was still the second-highest in the company's history.

Nio's deliveries in August included 12,015 SUVs and 7,314 sedans, it said, without disclosing specific delivery figures for different models.

Nio currently sells the ES8, ES7, ES6, EC7, ET7, ET5, ET5 Touring, of which the first four are SUVs and the last three are sedans.

In the January-August period, Nio delivered 94,352 vehicles, up 31.86 percent year-on-year.

As of August 31, Nio's cumulative deliveries since inception reached 383,908 vehicles.

Nio's lower deliveries in August may be related to a brief production halt at its F1 plant from late July to early August for upgrades.

Nio's F1 plant stopped production for five days from July 29 to August 2 for a production line upgrade, according to an August 21 report by local media outlet Caixin.

Nio's vehicles are produced at two factories in Hefei, Anhui province in eastern China, including the F1 plant, the JAC Nio advanced manufacturing base, and the F2 plant in NeoPark.

Originally, both the old ES6 and ES8 were produced at the F1 plant, but to ensure capacity, the F1 plant is now mainly producing the new ES6, while production of the new ES8 has been moved to the F2 plant, according to Caixin.

Nio was seeing at least 300 ES6s roll off the production line every day, and some of its workshops have switched from single-shift to two-shift production, Caixin said in the report, citing a person familiar with the company's production line.

Nio plans to release and start delivering the EC6, a newly upgraded mid-size coupe SUV, in September, completing the full product switchover based on the NT 2.0 platform, the company said in an August 29 analyst call after announcing its second-quarter earnings results.

The company guided for third-quarter deliveries of 55,000 to 57,000 units in the earnings report, implying year-on-year growth of about 74.0 percent to 80.3 percent.

New report reveals what steps Nio has taken to boost sales