Chevy Volt batteries are made by LG, originally in Korea but I think they now have a plant in Michigan.
Another is the quite significant investments Dyson are making in EV technology; they plan to build an EV car by 2020 but details are sparse.
Probably the most significant, however, is Swiss engineering group ABB, who plan to build Europe’s largest lithium-ion battery factory in Sweden targeting annual cell production equivalent to 32 gigawatt-hours by 2023, over 90 percent of Tesla’s Gigafactory target. [0]
[0] http://new.abb.com/news/detail/2121/abb-and-northvolt-partne...
The current estimate 150 GWh by 2020 (https://insideevs.com/elon-musk-says-gigafactory-output-coul...).
Which is kind of needed to build as many cars as they want.
Only half of batteries will go to cars (the other half to residential powerpacks and commercial deployments like the one in Australia) which is 75 GWh.
At average 75 kWh batter per car, it's just enough to build 1 million Tesla 3 cars a year, which is not that much and well within Tesla's projections by 2020.
That doesn't include even more battery hungry Tesla trucks and roadsters and S and X, which is why it's safe to say that before 2020 Tesla will have to start building another Gigafactory to deliver the cars they've already promised.
I don't know what the car market is like where you live, but where I live the majority of people only buy used cars (because of the lower cost). This is possible because of a surplus in supply of once-new cars. If we're going to get past the tipping point for electric cars, I'd suggest we'd need to see one of three things happen:
1. New electric cars sold at a price point that can compete with the used car market.
2. An increase in popularity in electric car conversions (whether DIY or done by a professional).
3. Wait until the early electric car models trickle down to the used car market.
We haven't seen how this will hit say, stuff like the bolt, but basically everyone but tesla got hit was outrageous depreciation.
If that keeps up, electric cars could become a similar price choice for a lot of people who don't need to drive all that far, even if they're the earlier low-range models. This could be further incentivized by stuff like free HOV access and free charging some places a lot of locations enjoy.