Longer warranty don't necessarily mean the product is any better, cheaper or lasts longer. Car manufacturers bake the expected warranty costs into the price, so it is prorated into the cost of the vehicle. Have seen some reports online that replacing a Tesla battery can cost as much as $22,000. Apparently replacing individual failed cells is possible, but you need to take it someplace where they have the skill/knowledge to do this. Not sure if that type of repair might void any remaining warranty. All car companies selling electric vehicles tend to avoid talking about the limitations or trade-offs of such types of vehicles.
Will be interesting to see how the battery life might impact a car's residual value when you go to trade it in. Lead acid car batteries used to start internal combustion engines are an insignificant cost of the car and a lot different from lithium ion batteries that power electric vehicles which is likely the single most costly component on that vehicle. Certainly all car companies who make electric vehicles are working to improve the range/economics/battery life, etc. How much is actually possible vs the bluster you get from some is yet to be seen.
With other types of rechargeable batteries, using a higher voltage charger reduces battery life. Not seen any articles that assess potential battery life for lithium car batteries based on which charging method is used, so will be interesting to see how that plays out. Real-world battery experiences can often be much different from what is seen in a laboratory.