So far the story of Tesla Motors has been about exciting electric luxury cars and an even higher performing stock.

Next week it will reveal plans for a much less sexy innovation that is more important to the company's future than either of those things: A huge new lithium battery factory dubbed the "Gigafactory" by Tesla founder Elon Musk. The plant is the key Tesla needs in order to produce an "affordable" long-range electric car in substantial enough numbers to join the ranks of the major automakers.

"It's the future of the company," said Craig Irwin, analyst with Wedbush Securities. "They need to cut the cost of the battery in half in order to make a half-million cars. This is how they are going to do it."

The size of the plant will be massive. Musk predicted in November that it would have a capacity equal to all factories making lithium ion batteries around the globe. That includes lithium batteries going into Teslas as well as laptops, tablets and smart phones.

Panasonic (PCRFF), currently Tesla's primary battery supplier, is likely to be a partner in the plant.

Tesla (TSLA) has repeatedly said that it would already be selling more cars, and growing even faster, if it wasn't constrained by the limited supply of batteries.

Tesla's goal has always been to sell a mass-market car priced in the $30,000 to $40,000 range that can travel long distances on only an electric charge. The Model S, Tesla's current car, can go more than 200 miles between charges but has a starting price of $69,000. Musk said the new plant will allow the company to meet its goal of releasing the mass-market car within three years.

Investors were excited after Tesla upped its 2014 sales target to 35,000-vehicles. Tesla wants to sell more than 10 times that many of the next generation car. That would dwarf all electric passenger vehicles now on the market. And it would propel Tesla from a niche luxury brand to become a major player among even traditional carmakers.

Related: Tesla plans sales of 35,000 cars in 2014

"Over the time I've covered the company. I have seen an evolution," said Ben Kallo, analyst with Baird & Co. "It started out as a dream. Now the mentality I see in the company is they believe they're close enough to change the whole industry in the next 10 years to the point where electric cars are the preferred mode of transportation."

The company has given no clues about the cost of the plant, though Musk suggested Wednesday the company may issue more shares of its high-flying stock to raise some of the cash it needs to build it. Kallo thinks the plant could cost $2 billion to $5 billion. Irwin says the cost could top $10 billion.

It also has not disclosed anything about the location of the plant but there are published reports that the company has been looking at sites the Southwest United States.

Related: Tesla surges in Consumer Reports' best-liked car ranking

Tesla will likely swallow up the lion's share of the output of the Gigafactory, although it has said it will sell some of the batteries to the solar power industry for storing energy collected during the course of a day. Musk is also chairman of a solar panel company, SolarCity (SCTY), which is run by his cousins.

"We believe the days when Tesla is known purely as an auto company are numbered," said Adam Jonas, analyst with Morgan Stanley.