I see that the Tesla battery pack weighs 1,200 pounds. Reducing weight greatly improves efficiency, handling, braking, and acceleration, meaning lighter weight is all around better. It seems a bit wasteful of weight and materials to have 7,000 metal casings around 7,000 tiny batteries, connected with thousands of connections, rather far fewer larger cells. I'm surprised they don't use perhaps 24 or 100 larger cells instead, thereby eliminating thousands of unnecessary casings and connections.
There are a number of reasons.
1. 18650 cells are the cheapest per kWh, significantly so.
2. The smaller cell size helps with thermal management. It's easier to deal with the heat from using the batteries the smaller they are. There have been problems with airlines that use larger cells with them catching fire.
3. Power capability is actually higher with smaller cells. For a car with the acceleration of a Model-S, this is important.
4. Due to the amount of R&D into the cell, which is the most common LiIon cell in the world, weight and volume wise it's at least as energy dense as anything else, extra casing or not.
5. The connections aren't actually that big of a deal, most of the batteries are simply end-to-end.
But bear in mind my driving occasionally includes a 12 mile stretch of twisty country lanes that leave the brakes smoking.
That would do it. What can I say, it was a forum post, the 'under normal usage' should have been implied. People do not normally smoke their brakes that often.
Nope, built in volume (100K/yr) in a factory in Zhuhai. Using a TI amplifier ($1.20/100K pieces), AKM DAC ($1.00 for a good quality unit, 100K pricing). Regulators ($0.70 - need 3.3V and 1.8V, LDOs are cheap but not that cheap), passives (another $0.40, driven mainly by caps), connectors, mechanicals (squirt a part, shoot a little paint, you're at $0.50 in 250K pricing). It's not cheap - which is why there is a STRONG market for counterfeit IAP2 chips, and many who don't pay the appropriate licensing fees, and many who use raw plastic finish (screw flow and knit lines), improper connectors (fake Lightning connectors with questionable tolerancing), etc.
This isn't just "an adapter" - it also would need to have a full DAC and amplifier inside, as well as a power supply. So it's more than the simple connector/wiring adapters you're thinking of.
But if your brand new $200 Beats won't plug into your MacBook, that's a problem.
It's OK, there will be a $29 dongle to fix that...
16.5 feet in the Twilight Zone = 1 Rod Serling