Every lithium ion battery makers woke up last week, on the Friday morning, and hoped that it had all been a bad dream. But unfortunately Tesla had rained horribly on their parade, taking the fight to battery makers everywhere and redefining the global economics of lithium ion batteries. While most US investors saw Tesla’s Battery day as a damp squib last week, which ripped $25 billion off the market cap of the Tesla stock, there will have been hastily called board meetings happening around the globe as upwards of 50 or 60 companies – and yes $ billions are at stake – and each of them tried to wrestle with the numbers that define the new reality. Some were venture…