Writing down $100M+ in battery inventory would be a big hit, especially with their profit margins being thin, but I wouldn't consider it a big shock. At $20000

Writing down $100M+ in battery inventory would be a big hit, especially with their profit margins being thin, but I wouldn't consider it a big shock. At $20000 per pack, $100M+ in battery inventory is 5000+ cars, which is less than a percent of total production so far. Having a significant number of defects early in the production process is common. Ultimately, it's up to them how to value it, within reason and the law, just like it's up to them when to sell emissions credits.