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Car companies, starting with Volvo last summer, have laid out plans to electrify entire lineups of vehicles. But the fine print makes it clear that the coming decade and beyond will focus not just on massive battery packs powering electric motors, but also on adding a little extra juice to the venerable internal combustion engine.
Increasingly, that juice will arrive in the form of new electrical systems built to a 48-volt standard, instead of the 12-volt systems that have dominated since the 1950s. Simpler than Prius-type drivetrains and less expensive than Tesla-scale battery power, the new electrical architecture both satisfies the demands of cars made more power hungry by their gadget load and enables the use of lower-cost hybrid drive systems.
https://www.nytimes.com/2018/02/08/business/electric-cars-48-volts.html
(Score: 3, Informative) by anubi on Monday February 26 2018, @07:15AM (3 children)
I just hope they don't start using aluminum wire!
Looked at any modern washing machine motors? Aluminum wire! With orange lacquer so it LOOKS like copper.
I found that out when I decommissioned a machine with a rusted out tub. While I did recover several handfuls of nice colored wire for my projects, what became a firepit, and a mount for a sink I wanted for the back yard, I had kept the motor as a donor for copper wire that I like for things like tying plants. To my chagrin, when I ground the motor open to get to the wire wound on the stator, the wire itself was aluminum!
No problem for me, and the motor did not fail because of this, but I found it interesting that the motor was wound with orange-lacquered aluminum wire. Pretty obvious when I took a small file to it.
Also, note a lot of the "Heavy Duty 4 Gauge Jumper Cables" look like copper. Look for "CCA". I know, we automotive types see CCA and think "Cold Cranking Amperes". That's not what the manufacturer of those cables meant. "CCA" is their term for "Copper Clad Aluminum". That's right, Aluminum wire in your battery jump cables. That nice low-gauge rating may not mean as much as you was hoping it meant.
"Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]
(Score: 2) by deimtee on Monday February 26 2018, @10:24AM (2 children)
Aluminium is less ductile and less dense than copper, but per linear mass is both stronger and a better conductor. Per unit volume copper is almost twice as good as a conductor, but is three times heavier.
Fixed wiring as in a motor probably should be aluminium, it would reduce the total weight.
One of the main reasons for not using it is actually the problem of terminations. It is difficult to reliably connect to as the surface oxide layer is basically sapphire. CCA sounds like an interesting solution to that.
CCA Jumper cables, yeah those cheating fuckers need a few CCA's through their privates. Aluminium wire will crack if repeatedly flexed as happens to jumper cables.
If you cough while drinking cheap red wine it really cleans out your sinuses.
(Score: 2) by Grishnakh on Monday February 26 2018, @03:53PM
Fixed wiring as in a motor probably should be aluminium, it would reduce the total weight.
I doubt that. Motors have two main parts: the windings and the core (this applies to both the rotor and the stator, though some motors omit windings in the stator and use permanent magnets). The core is usually made of thin laminations of iron, and is used for conducting magnetic flux. Using aluminum windings would require you to significantly enlarge the whole motor, including the core, which means you'll be adding a bunch more mass in iron, which is even more dense than copper.
Iron is cheap, though, so for cost-sensitive applications where you care more about cost than size, and weight isn't a big concern, it can make sense. A laundry machine is a good example of such an application: heavier is actually better here usually (modern washers actually add concrete to increase mass), and there's generally plenty of room for a motor. But in a car, even if the motors weigh the same, size is much more important than shaving a few pennies of cost.
(Score: 2, Informative) by Anonymous Coward on Monday February 26 2018, @04:25PM
Copper has the same problem. Neither metal has a fatigue limit -- i.e., both copper and aluminum will inevitably fail under cyclic loading/unloading (no matter how small the load). Aluminum does fail faster, though. If you don't use your jumper cables more than a couple times a year (like most people) then either kind could last a lifetime.
So as with most things in life, it's a cost/benefit tradeoff. CCA should have a substantially lower upfront cost. It will also weigh less, which might be an advantage (keeping it in your car -> less mass -> less fuel consumed? This effect is probably in the noise).
On the other hand, aluminum is thicker than copper for the same conductivity, so CCA cables will be physically larger. Also your copper cables will probably be worth something in scrap later while the CCA cables will probably be worthless.