Tesla First To Abandon 12V Electrical

[Chance]

This could be a big step towards switch from 12- to 48-Volt low-voltage vehicle architecture, potentially filtering down to most vehicles including ICE-driven chassis used for motorhomes.

https://rvbusiness.com/cybertruck-cy...rical-systems/

Tesla claim 48V electrical will be used on upcoming Cybertruck and other future models, replacing the previous 12V systems they have used like every other manufacturer for decades (about 60 years).

No doubt it should be easier for Tesla since they are 100% electric vehicle manufacturer, and therefore don’t have to deal with standard charging systems (alternators) and many ICE-related sensors and controls. Tesla is also more vertically integrated, so can control design and manufacturing revisions easier.

It’s hard to say if such a move will pressure other manufacturers to also switch from 12 to 48 Volts. That’s a lot of stuff that must be changed, from electronics, power window motors, light, radios, etc. The list is almost endless.

Thoughts on 48V making it to conventional RV chassis?

[EA37TS]

Originally Posted by Chance

This could be a big step towards switch from 12- to 48-Volt low-voltage vehicle architecture, potentially filtering down to most vehicles including ICE-driven chassis used for motorhomes.

https://rvbusiness.com/cybertruck-cy...rical-systems/

Tesla claim 48V electrical will be used on upcoming Cybertruck and other future models, replacing the previous 12V systems they have used like every other manufacturer for decades (about 60 years).

No doubt it should be easier for Tesla since they are 100% electric vehicle manufacturer, and therefore don’t have to deal with standard charging systems (alternators) and many ICE-related sensors and controls. Tesla is also more vertically integrated, so can control design and manufacturing revisions easier.

It’s hard to say if such a move will pressure other manufacturers to also switch from 12 to 48 Volts. That’s a lot of stuff that must be changed, from electronics, power window motors, light, radios, etc. The list is almost endless.

Thoughts on 48V making it to conventional RV chassis?

Golf carts have been 48VDC for years. Electrical accessories can stay 12VDC using a transformer or similar item.

RV is way too heavy for electric drivetrain. Long distance travel not possible and has issues with current EVs and the charging infrastructure.

[ducksface]

.02 second Google search of stuff I already knew.

https://www.google.com/search?q=48v+...e-gws-wiz-serp

When companies post
Hey! Look at me!
Worthlessness,
It's so they can get the next payment on thier grants. It supposedly proves the progress required for payment.
Not a person in the whole world is swayed to buy stock or car based on such an announcement.
It fulfills a banking requirement not a consumer need or want.
It doesn't have to be valuable, it just has to check a box on a time based or discovery based chronological list.

And
I truly hope I didn't misunderstand and you are really trying to open up another;
What if
Electric RV
Thread

[Lt Keefer]

I know it's Musk's business model to tinker with older technologies, but unless you count tax burden, he really adds nothing to our society. Instead of shifting the negative aspects of using ICE to the third world someone should be working on how to lessen those negatives of the ICE.

[16ACE27]

Originally Posted by Chance

This could be a big step towards switch from 12- to 48-Volt low-voltage vehicle architecture, potentially filtering down to most vehicles including ICE-driven chassis used for motorhomes.

https://rvbusiness.com/cybertruck-cy...rical-systems/

Tesla claim 48V electrical will be used on upcoming Cybertruck and other future models, replacing the previous 12V systems they have used like every other manufacturer for decades (about 60 years).

No doubt it should be easier for Tesla since they are 100% electric vehicle manufacturer, and therefore don’t have to deal with standard charging systems (alternators) and many ICE-related sensors and controls. Tesla is also more vertically integrated, so can control design and manufacturing revisions easier.

It’s hard to say if such a move will pressure other manufacturers to also switch from 12 to 48 Volts. That’s a lot of stuff that must be changed, from electronics, power window motors, light, radios, etc. The list is almost endless.

Thoughts on 48V making it to conventional RV chassis?

Not in my lifetime, maybe not my son's.

What is the advantage of moving to 48 VDC in the chassis? Higher voltage has one main advantage - lower current so thinner wires.
It also has one main disadvantage - more dangerous - both to humans and as a fire hazard (sparking). 12 VDC in most case will not produce enough current to kill a human, 48 VDC can easily reach that current threshold.

So to make an industry wide move the advantages have to outweigh the disadvantages.

48 VDC will make it to the house side of the RV long before vehicle manufacturers wil test their toes in that water.

[Beau388]

Originally Posted by 16ACE27

Not in my lifetime, maybe not my son's.

What is the advantage of moving to 48 VDC in the chassis? Higher voltage has one main advantage - lower current so thinner wires.
It also has one main disadvantage - more dangerous - both to humans and as a fire hazard (sparking). 12 VDC in most case will not produce enough current to kill a human, 48 VDC can easily reach that current threshold.

So to make an industry wide move the advantages have to outweigh the disadvantages.

48 VDC will make it to the house side of the RV long before vehicle manufacturers wil test their toes in that water.

It took about 6 years for cars and small tractors to move from 6 volts to 12 volts. Modern alternators will produce any need voltage from 6 volts to about 140 volts. It just depends on the voltage regulator.



Watts (power) are I^2 (squared amps) x R (ohms). So if for the same wattage, if you quadruple the voltage to 48 volts, you reduce the amperage by 16 times. This allows alternators, generators and electric motors to be smaller, more efficient and cheaper. That the wiring required is smaller to carry the same wattage is a benefit, but minuscule when compared to those rotating electrical elements in the circuits.
Cars voltage developed around the need for a small FLA battery that could stand up to off road use. Now that plastic AGM batteries are ubiquitous, a single 24 cell AGM battery in a group 27 size is definitely possible. After all it they are available for golf carts, why not use them in cars or motor homes.

[16ACE27]

Originally Posted by Beau388

It took about 6 years for cars and small tractors to move from 6 volts to 12 volts. Modern alternators will produce any need voltage from 6 volts to about 140 volts. It just depends on the voltage regulator.



Watts (power) are I^2 (squared amps) x R (ohms). So if for the same wattage, if you quadruple the voltage to 48 volts, you reduce the amperage by 16 times. This allows alternators, generators and electric motors to be smaller, more efficient and cheaper. That the wiring required is smaller to carry the same wattage is a benefit, but minuscule when compared to those rotating electrical elements in the circuits.
Cars voltage developed around the need for a small FLA battery that could stand up to off road use. Now that plastic AGM batteries are ubiquitous, a single 24 cell AGM battery in a group 27 size is definitely possible. After all it they are available for golf carts, why not use them in cars or motor homes.

Might want to recheck your math.

Power (watts) is E x I
For the same power, quadrupling voltage cuts current to 1/4, not 1/16.

Now power losses in the transmission wire will go down as those power losses are defined by the I(squared)R equation so 1/4 squared is 1/16 the power losses.

[Chance]

To be clear, this has nothing to do directly with battery electric vehicles, so we can skip repeating that discussion.

Originally Posted by 16ACE27

Not in my lifetime, maybe not my son's.

What is the advantage of moving to 48 VDC in the chassis? Higher voltage has one main advantage - lower current so thinner wires.
It also has one main disadvantage - more dangerous - both to humans and as a fire hazard (sparking). 12 VDC in most case will not produce enough current to kill a human, 48 VDC can easily reach that current threshold.

So to make an industry wide move the advantages have to outweigh the disadvantages.

48 VDC will make it to the house side of the RV long before vehicle manufacturers wil test their toes in that water.

Why 48V? When vehicles started using more and more electricity, GM and others in the late 1990s, if I recall correctly, proposed a 36V nominal with 42V charging electrical system. There wasn’t much cooperation between manufacturers and the proposed standard never took off.

Much later, Europeans determined 60V was safety threshold to humans for low-voltage applications, and agreed amongst many companies to make 48V the future. It has already been in use for years in mild hybrids where +/- 15~20 kW or higher motor/generators are common.

If I recall correctly, they expected that initially a 48-12 DC-DC converter would be used until the entire vehicle’s electrical system converted over to 48 VDC. The 48-12 converter was discussed/reported as an interim solution.

If or when ICE vehicles convert electrical architecture to 48VDC, everything in the vehicle will be at one voltage, so no need for DC-DC converter. Alternators that are now pushing 250 Amps can go back to ~60 Amps, or even higher if needed.

There is little doubt that with new loads like electric power steering and dozens of computers, new cars need a lot more juice than they needed 60 years ago. Advantages may include higher power capability, greater efficiency, lower cost, lower weight, etc. Yes, each of these are relatively minor as percentage of total load, but every bit helps.

As far as safety, Volta and Xantrex already have 48+ house systems, not to mention golf carts and house solar have been using 48VDC for decades without too many electrocutions that I’m aware of.


P.S. — Power tools and E-Bikes also, so apparently safety hasn’t discouraged adoption in other areas.

[ducksface]

I'm not really understanding the discussion.
If you didn't know greyhound busses and planes and some military and some boats and lots of equipment(I think my merkur scorpio had one or two 24v circuits) use other than 12v....




So,what is the discussion?
48 vs why? A real why, not a press release speculation.
And
Unless there is an option checkbox, you'll get what you get.

Wire weight will affect the purchase order for 10,000,000 feet of wire. It will not affect anything else in a measurable value sense. Your part of this excercise will be more 3xpensive and multiple batteries.


Let me know why I should care about, or how I can affect, this any more than I would fine thread vs coarse thread on the cigarette lighter plug.

I sway easily. Convert me.

[16ACE27]

Originally Posted by Chance

To be clear, this has nothing to do directly with battery electric vehicles, so we can skip repeating that discussion.





Why 48V? When vehicles started using more and more electricity, GM and others in the late 1990s, if I recall correctly, proposed a 36V nominal with 42V charging electrical system. There wasn’t much cooperation between manufacturers and the proposed standard never took off.

Much later, Europeans determined 60V was safety threshold to humans for low-voltage applications, and agreed amongst many companies to make 48V the future. It has already been in use for years in mild hybrids where +/- 15~20 kW or higher motor/generators are common.

If I recall correctly, they expected that initially a 48-12 DC-DC converter would be used until the entire vehicle’s electrical system converted over to 48 VDC. The 48-12 converter was discussed/reported as an interim solution.

If or when ICE vehicles convert electrical architecture to 48VDC, everything in the vehicle will be at one voltage, so no need for DC-DC converter. Alternators that are now pushing 250 Amps can go back to ~60 Amps, or even higher if needed.

There is little doubt that with new loads like electric power steering and dozens of computers, new cars need a lot more juice than they needed 60 years ago. Advantages may include higher power capability, greater efficiency, lower cost, lower weight, etc. Yes, each of these are relatively minor as percentage of total load, but every bit helps.

As far as safety, Volta and Xantrex already have 48+ house systems, not to mention golf carts and house solar have been using 48VDC for decades without too many electrocutions that I’m aware of.


P.S. — Power tools and E-Bikes also, so apparently safety hasn’t discouraged adoption in other areas.

But all those items use closed supply - both the + and + sides are completely insulated. Unlike the chassis of most vehicles that have exposed + terminals at may locations and the - is exposed everywhere. The + is not as exposed as it used to be decades ago, but you can still easily inadvertently use your body to short the + and - of a vehicle's power system.

[Chateau_Nomad]

12 volt vs 48 volt safety... if there's enough amperage available, a dead short will deliver more than ample lethal current. Maybe that's why it's called a dead short? If you're not feeling lucky, install a catastrophic terminal fuse on the battery.

[Chance]

Originally Posted by Chateau_Nomad

12 volt vs 48 volt safety... if there's enough amperage available, a dead short will deliver more than ample lethal current. Maybe that's why it's called a dead short? If you're not feeling lucky, install a catastrophic terminal fuse on the battery.

12V has never shocked me even when holding bare jumper cables in each hand. Honestly, on the farm most large tractors were 24V and that didn’t shock either. Batteries were capable of 1,000 Amps but my resistance is too high to allow significant current to flow through my body. With batteries, current capacity differences doesn’t really matter much since practically any of them can supply enough current to kill, but fortunately the voltage isn’t usually high enough to force enough current to hurt us.

I’d bet most people would feel 48V, and especially 56V or higher during charging. I don’t want to find out.

[Chance]

Originally Posted by 16ACE27

But all those items use closed supply - both the + and + sides are completely insulated. Unlike the chassis of most vehicles that have exposed + terminals at may locations and the - is exposed everywhere. The + is not as exposed as it used to be decades ago, but you can still easily inadvertently use your body to short the + and - of a vehicle's power system.

Good points. Maybe they are counting on most buyers not checking anything in the first place. With Tesla, there is up to 800 Volts in vehicles so I doubt DIY mechanics will do much tinkering.

You make good argument in that something as simple as a light bulb change would have some exposure. I’ll assume engineers can provide adequate protection.

[Chance]

Originally Posted by ducksface

….cut…

I sway easily. Convert me.

Not trying to convert anyone. Just sharing news I find to have potential to improve future RVs. I don’t care much about general chassis going from 12 to 48 Volts across the auto industry, but the implication for RVs to have more power at lower costs is a big plus.

You have seen plenty of threads with RVers wanting more and more lithium battery capacity, but one of the limitations is that the more you have, the more you have to charge. Also, high power items like inverters and DC air conditioners will operate better at 48V than 12V. It’s the future, which is why Volta went with 48V nominal from start, and others like Xantrex who laughed are now introducing their version also.

Anyway, the main disadvantage to building a 48V RV electrical system today is that you have to install a very expensive 48V alternator, or else add a DC-DC step-up converter; which limits charging speed.

A factory 48V high-capacity alternator could solve the problem of charging a large lithium battery bank with higher reliability and at a much lower cost.

Those still not convinced more power is needed, or at least wanted by many, just consider some OEM dual-alternator options are up to 500 Amps total. That’s a long ways from my 60 Amp in an old classic car. Not a Scorpio — sold that one many years ago.

[Judge]

Originally Posted by EA37TS

Golf carts have been 48VDC for years. Electrical accessories can stay 12VDC using a transformer or similar item.

RV is way too heavy for electric drivetrain. Long distance travel not possible and has issues with current EVs and the charging infrastructure.

Don't be too sure and don't count out Musk....

Tesla built and tested an EV semi with a simulated loaded weight of 40 tons.... and it went 500 miles on a single charge.

Might not happen in our lifetime but as technology changes and improves, an all-electric motorcoach is not out of the question.

[Judge]

Originally Posted by Chance

P.S. — Power tools and E-Bikes also, so apparently safety hasn’t discouraged adoption in other areas.

You are correct. My Pedego e-bikes use a 52V battery.


When I upgraded to LiFePO4's two years ago, I went with BigBattery. Since then they have really expanded their 48V offerings and they have a 72V offering as well.

https://bigbattery.com/by-voltage/#48


BigBattery offers a complete 48V kit for off-the-grid living that is 28kWh and can power a 5 - 7 room home.


https://bigbattery.com/products/48v-...em-power-plus/


I agree with you that 24V or 48V could end up becoming the standard for powering an RV. The evolution and adoption of LiFePO4 batteries and weight savings has opened the door to move away from 12V for larger power demands like powering an RV.


Here is a good article about 12V vs 48V and it mentions RV's:

https://getlitbatteries.com/12v-vs-4...h-do-you-need/


In retrospect.... had I spent a little more time planning, I should have gone with a 48V BigBbattery LiFePO4 option myself. It would have been cheaper and required less space ultimately.

[lwmcguire]

Our GEM cars were 72v 20 some years back

Used 6 12v Gel or AGM, although FLA was a cheaper option

They have on board chargers

Newer models offer lithium and solar options

Was careful changing batteries and never tried to get shocked

[Chance]

Originally Posted by Judge

You are correct. My Pedego e-bikes use a 52V battery.


When I upgraded to LiFePO4's two years ago, I went with BigBattery. Since then they have really expanded their 48V offerings and they have a 72V offering as well.

https://bigbattery.com/by-voltage/#48


BigBattery offers a complete 48V kit for off-the-grid living that is 28kWh and can power a 5 - 7 room home.


https://bigbattery.com/products/48v-...em-power-plus/


I agree with you that 24V or 48V could end up becoming the standard for powering an RV. The evolution and adoption of LiFePO4 batteries and weight savings has opened the door to move away from 12V for larger power demands like powering an RV.


Here is a good article about 12V vs 48V and it mentions RV's:

https://getlitbatteries.com/12v-vs-4...h-do-you-need/


In retrospect.... had I spent a little more time planning, I should have gone with a 48V BigBbattery LiFePO4 option myself. It would have been cheaper and required less space ultimately.

Judge, glad to see availability of Big Battery has improved, and that prices have stabilized. Their cost at under $400 per kWh is not bad at all, and much cheaper than premium US brands.

A little research on this topic suggests some in the industry expect consolidation of low-voltage to 48V by 2030. I’m not sure it will transfer to ICE vehicles that fast if manufacturers are forced to abandon them soon after that, but I don’t see that happening by 2035 anyway. If future is not clear, manufacturers won’t invest in upgrading ICE vehicles to 48V to then walk away a few years later.

Like many things, 48V started slowly initially, and is picking up speed. Initial 48V (nominal) standard was approved in 2014 in Europe, and in 2017 two mild hybrid cars using 48V motor/generators were introduced. In 2018 four more, and in 2019 sixteen more (per one report). All used DC-DC converters to retain 12V system during transition.

Recently, an ISO 48V standard was approved which should help with adoption speed by eliminating ambiguity for equipment designers and manufacturer.


Regarding RVs, I believe that the “possibility” of 24V systems has really hurt progress towards higher-than-12V adoption. At least no one talks about 36V much any more.

I know 24V was (or is) common on larger diesel vehicles, so there was already interest for that. There are some 24V inverter/chargers, some small 24V refrigerators used in semis and boats, etc., but growth in 24V seems to be stalling in favor of 48V, as should be. The faster 24V is left behind, the faster manufacturers of refrigerators, inverter/chargers, air conditioners, etc. will concentrate on new 48V designs. Market ambiguity tends to hold businesses back for obvious reasons.

Don’t get me wrong, there are some advantages to 24V over 48V, but not enough to delay moving towards 48V. In my opinion, we should stay at 12V or make a big jump to 48V, but no middle ground. Agreement on a single new standard is critical.

Below is one prediction. Not sure I agree with timing, but agree with need to consolidate to a single voltage to make systems as simple as possible.
.

[Muggs]

When 12 volt not enough, we have 16 volt option in racing. Not all that much different in past when 8 volt was an upgrade over 6 volts. My son asked why my ancient "Western Auto" battery charger had 6, 8 and 12 volt settings.

Times change, things change.

I have been tickled by 12 volts. I been nailed pretty solidly by 36 and 48 volt forklift systems. Sweaty outside in florida gives good conductivity. Horse fence voltaga was inow side but really stung.

Welding voltages can range from 50's to 100 depending on load. That really hurts.

Lighter wiring an advantage. Noticed a trend to higher voltage in industdial control systems recent years.

[ducksface]

If I could drive any car without having to maintain it myself
The Scorpio is #1 on my list
A Citroen SM is next.

I loved that Scorpio as a driver more than any car I've ever had.

I now understand some of the conversation.
Thanks.

I did not know about 16v oddesey batteries.
I turned down a newer one at an estate sale because I thought it was running away at 15.9 volts. Itbsure woulda turned my 2220 weber'd vw.