Tesla Motors has now completed upgrades to its Fremont, California, plant ahead of an expected production increase.

The electric car-maker shut down the factory for two weeks in late summer to complete modifications to handle the addition of the all-wheel drive Dual Motor Model S.

The company says the added capacity also helps it accommodate stronger global demand, and the eventual start of Model X crossover production.

MORE: Tesla, BMW Chat Over Possible Partnership, Elon Musk Says

Tesla detailed the upgrades in a recent company blog post, saying they'll help it raise production by 50 percent by the end of 2015.

By its own estimation, Tesla built 22,000 cars last year and is on track to build 35,000 this year.

Tesla factory, Fremont, California

Tesla factory, Fremont, California

So the company's total 2015 production could be 85,000 cars or more.

That number will include some Model X electric crossover utility vehicles, but the bulk of the cars built are still likely to be Model S sedans.

Earlier this month, Tesla said it would delay first deliveries of the Model X until the third quarter of 2015.

ALSO READ: Tesla Model X Delayed Again, Model S Sales Highest Ever: Third Quarter Report

The assembly-line and plant changes mostly focus on automation, including robots that can lift entire cars into position for different stages of assembly and install their battery packs.

These robots are named after X-Men characters because, Tesla says, "to us, these robots are like superheroes."

A dedicated assembly area was also added for the Dual Motor Model S, including a largely automated line for assembling the cars' model-specific drive units.

2012 Tesla Model S beta vehicle, Fremont, CA, October 2011

2012 Tesla Model S beta vehicle, Fremont, CA, October 2011

Other efficiency-related improvements were made as well, including new conveyors and robots in the plant's its battery-cell processing, and more welding equipment for body assembly.

However, the Fremont factory complex can support far greater volumes than those planned by Tesla for next year.

RELATED: Largest Auto-Industry Employer In California: Electric-Car Maker Tesla Motors

Before it built Tesla electric cars, the plant was used by New United Motor Manufacturing, Inc. (NUMMI), a collaboration between General Motors and Toyota.

At its height, the Fremont facility built up to 500,000 cars per year--largely compacts like the Geo Prizim and Pontiac Vibe.

Tesla's still a long way from seeing those numbers, but at least it will have the capacity available if and when it does.

_______________________________________________

Follow GreenCarReports on Facebook, Twitter, and Google+.