An example of a battery factory powered (eventually) by 100% renewable energy is the Gigafactory using a combination of wind and solar. Even today, it is entirely powered by electricity. It doesn't even have a gas line (as would be common for any large building, especially an industrial one). Its solar roof is eventually going to be 70MW. They've just started installing part of it, and from satellite and aerial imagery it looks like they have a few Megawatts already installed.
And assuming the vast majority of the energy used in battery production is electricity, then the figure for emissions that you used is highly dependent on grid mix. For instance, coal is roughly 1kg of CO2 per kWh. The current US grid is less than half of that (~430grams/kWh by my calculations using data through December 2017). If your study assumed coal power for battery production and assuming the Gigafactory is no more efficient (doubtful), then even today before the solar roof is installed, the CO2 emissions is already closer to ~90kg of CO2 per kWh of capacity. The grid is improving roughly 4% per year, and the Tesla Gigafactory roof and wind turbines coming online should drop that even more.
...especially as the Gigafactory starts buffering its own electrical load with its own batteries to reduce the cost of its grid connection and transportation of the batteries and components is increasingly done with Tesla Semis.
And assuming the vast majority of the energy used in battery production is electricity, then the figure for emissions that you used is highly dependent on grid mix. For instance, coal is roughly 1kg of CO2 per kWh. The current US grid is less than half of that (~430grams/kWh by my calculations using data through December 2017). If your study assumed coal power for battery production and assuming the Gigafactory is no more efficient (doubtful), then even today before the solar roof is installed, the CO2 emissions is already closer to ~90kg of CO2 per kWh of capacity. The grid is improving roughly 4% per year, and the Tesla Gigafactory roof and wind turbines coming online should drop that even more.
...especially as the Gigafactory starts buffering its own electrical load with its own batteries to reduce the cost of its grid connection and transportation of the batteries and components is increasingly done with Tesla Semis.
EDIT: Source: https://www.teslarati.com/tesla-gigafactory-1-solar-rooftop-...