Toyota's been claiming solid state batteries are just around the corner for 13 years.

• 2010: Toyota unveils prototype LiCO2 solid state cell. Predicts use in hybrids.
• 2012: Toyota unveils prototype Li10GeP2S12 solid state cell. Predicts mass production of 1000-km EVs in 2015-2020.
• 2014: Toyota claims to have achieved 400Wh/L in solid state prototype cells. They adjust range estimates to 500 km.
• 2017: Toyota predicts commercialization 2020-2025.
• 2019: Toyota predicts it will have functioning solid state EV prototypes by the Olympics.
• 2020: Toyota claims it already has a mostly-functioning prototype.
• 2021: Toyota's solid state EV is a no-show for the Olympics.
• 2022: Toyota claims solid state hybrids will be commercialized by 2025.
• 2023: Toyota claims it will have solid state batteries commercialized by 2027-2028. They still claim 1000-km range, but with the qualifier that the BZ4X is understood to have 500 km range today instead of the 300 km measured by 3rd parties. So they are effectively sticking to their 2014 range prediction.

Toyota may well produce a solid state battery, but they've moved the goalposts enough times that it would be foolish to take them at face value now.