Tesla have a new battery the 4680 which is said to be half the cost of the current Tesla 3 battery. They have also developed a way of integrating the battery into the chassis to reduce weight and provide the car with greater agility.
They talk of 500 mile range and recharging time of 35 minutes. However both Toyota and Neo are hoping to have solid state batteries ready by 2023 that will have a range of 1000 km or about 700 miles and recharge times of 18 minutes.
I don’t think the new Tesla will come in at £18000, rather between £20000 and £25000. Even so the improvements are significant and Musk is a canny businessman, if he can see a profit in Motability he will go for it. We live in interesting times.