"Battery passports" totrack the raw materialsused in making electriccar batteries are proposed as a way of enforcing environmentalregulations on mining world-wide. Critics question whether the systemgives the mining companies too much influence in the system, whichthey could use to cheat.I support the system for that purpose — but if businesses startoffering to change out your car's battery as a quick recharge, it iscrucial that those businesses not be able to examine the number ofthe battery that they get from you. That would become, in effect,another system for tracking where you drive.The same reasoning applies to ordinary charging systems for cars.They must accept anonymous payment and they must be forbidden to getany identifying data digitally from the car.