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[GoneToPlaid]

A peltier device is good if you want to cool something below ambient, and want it to be compact and have no moving parts. They are not very efficient. You also still need a very large heat sink for it to reject heat to air. Since the TC chargers work at up to 85C, they are well above ambient temp and a simple heat sink is plenty. Peltier devices will just suck power, add cost, and not help anything.

Also, you can't just soak heat into a block of material; you have to transfer that heat to the air. A 400W loss as heat for 1.25 hours is 0.5 kWh of heat, or 1,800,000 J. If you were just heating up a mass of material from 35C to 85C, you'd need this much:
Water 8.6 kg
Aluminum 40.4 kg
Copper 92.3 kg

The TC chargers have built-in thermal protection, so even if the heat sink gets loose or the fan fails, they won't catch fire.

TL;DR is that you have to move that heat into the ambient air. The simple way is with some aluminum fins and a fan, as TC does. TC uses a fan because it's needed to get the convection coefficient high enough. If you take the fan off, you'll be thermally limited in 30 to 45 minutes. You could do without a fan, if you made the heat sink something like 10x larger than the one with a fan.

Or do something kinda dumb like me and transfer the heat to water and dump it on the ground. It actually takes less water than in the above calcs because of evaporation sucking up a lot of heat.

Energicas have an oil cooling loop for the motor, controller, and now for the Experia the loop includes the AC charger. (as I understand it from reading about it a bit - not an owner). This is probably the path forward since one cooling system can be used all the time, whether riding or charging. Not much help for you, though.

[Specter]

IM glad they put the cooling loop on the AC charger, it's a HUGE step in the right direction.
Id love to see the built in AC charger be able to take 40 amps or so.  Imagine having 6k, 8, even 10k AC charge available!  The plug is a standard range plug so it's not something that would be very unique.  you could AC charge your bike in an hour or so, that'd be pretty near a game changer IMO.  No Bullshit with waah my CCS won't talk to this or that, if you can throw 40 -50 amps of 240 AC at it, and get your bike from 20 percent to 80 percent in around an hour, that's golden.

With water cooling the charger can easily handle it too.  Why don't they use the bikes inverter to charge the bike?  It does this on regen anyways, takes the AC from the motor turns to DC and puts back into battery.  Disable a few relays and just take 240 AC from the wall and rectify it back into the battery.  It's already got the water cooling in place, id think it'd be doable and possibly even shave a few pounds off the bike for the weight of the charger equip.

Just thinking out loud... yah I know, it's an annoying habit of mine
Aaron

[DonTom]

IM glad they put the cooling loop on the AC charger, it's a HUGE step in the right direction.
Id love to see the built in AC charger be able to take 40 amps or so.  Imagine having 6k, 8, even 10k AC charge available!  The plug is a standard range plug so it's not something that would be very unique.  you could AC charge your bike in an hour or so, that'd be pretty near a game changer IMO.  No Bullshit with waah my CCS won't talk to this or that, if you can throw 40 -50 amps of 240 AC at it, and get your bike from 20 percent to 80 percent in around an hour, that's golden.

With water cooling the charger can easily handle it too.  Why don't they use the bikes inverter to charge the bike?  It does this on regen anyways, takes the AC from the motor turns to DC and puts back into battery.  Disable a few relays and just take 240 AC from the wall and rectify it back into the battery.  It's already got the water cooling in place, id think it'd be doable and possibly even shave a few pounds off the bike for the weight of the charger equip.

Just thinking out loud... yah I know, it's an annoying habit of mine
Aaron

I charge my 2017 Zero SR at 8KW (~33 amps @240 VAC). The downside is I need to have an external charger in each of the sidecases.


-Don-  Reno, NV

[Specter]

so you are converting it to dc outside the bike and charging it, not plugging 240 into the bike, like the Ribelle does and having the bikes charger convert it for you correct?

Aaron

[DonTom]

so you are converting it to dc outside the bike and charging it, not plugging 240 into the bike, like the Ribelle does and having the bikes charger convert it for you correct?

Aaron

I do both, as I also use the OBC with AC in and the other two chargers with DC into the bike (to the battery contacts on the motor controller). Each DC charger is 3.3 KW and the bike is around 1.3 KW, so around 7.8 KW total if the AC voltage stays up under load.


I often need to hog up two J-1772s to get the full 7.8 KW, but I can also charge at less by not using the OBC or removing one of the external chargers or whatever I need to do since my system ignores the control pilot signal.



-Don-  Reno, NV

[GoneToPlaid]

Why don't they use the bikes inverter to charge the bike?

I've also thought about this, and the various manufacturers surely have as well. One reason we haven't seen it, at least with earlier bikes, is that both the motor controllers and chargers were more general-purpose devices made by outside vendors. Putting it all in one would be a custom design and require expensive R&D. Another possibility is that someone, somewhere is sitting on a patent to do this (but I haven't looked).

The other way to look at it is that DCFC is going to take over and be in every town and along every highway, so why spend a lot of money optimizing for AC charging that will never be all that fast?

[Specter]

DCFC is not going to  be mainstream ANYWHERE fast for at least a decade maybe more.  If the amount of cars on the road gets to the point where they think this is feasible, then we are going to have bigger problems when people are charging up at night, and the grid can not handle the extra load, and / or generation is not up to snuff on a cold night.

Look at Moronafornia, and the idiots in Texas who did NOT learn from Mfornia's mistakes, as a perfect example.  BIG push to put everyone on solar roofs, only they didn't get batteries, so anytime the grid farts hiccups or burps, all that solar goes into rapid shutdown and is useless until power is stable again for 5 minutes.  Then they can't even keep their lights on as it is, yet they want gigawatts of electric cars charging?  How is that going to work?  They already told people, well, we don't want you charging your car, we don't have the power.  With everything internet connected, I give it two years tops before those Nazi's mandate something where they can remotely disable your car / bike charging etc to make you 'comply'.  Sorry boss, can't come into work, my electric car is dead and I can't get it charged anywhere.  I had power in it but they took it overnight to keep my neighbors lights on for him.

Attempting to force people to comply by telling them, well you can only charge between these hours, or we will charge you stupid rates, is only going to piss people off.  I charge at 8 pm because thats when I get home from work, I don't have a CHOICE !! to charge up at noon.  Oh no problem, that 30K bike, just spend another 30k on a 30kw battery pack, charge it at noon then plug in when you get home.  oh don't forget the other 5k for the charger and electrician to hook it up, oh and the permit, environmental fees, bla bla bla.   NO incentive to get that bike now is there?

The unicorn farts and rainbow crowd need to wake up as to the realities of their perfect little green world.
Solar is NOT the solution to all our problems.
Wind only works in a very few areas.
Gas is nice but the gas transmission infrastructure is pretty much at max cap as it is, build new plants but can't get gas to run them ain't gonna work well.  Everytime they try to lay new lines, the same fools lock it up in court for years and years,  oh the scandanavian sea serpent tail snail lives there!! you can't disturb it!!
Nukes, havent had a new one in YEARS,  the one in georgia was supposed to have been online  4 or 5 years ago now, but is STILL playing games trying to get it going.

Even if tomorrow our genius' came up with a cheap car, cheap battery, everyone who can afford ice can afford this.. the power grid is  not ready to support it all yet.

Aaron

[MVetter]

Energicas have an oil cooling loop for the motor, controller, and now for the Experia the loop includes the AC charger. (as I understand it from reading about it a bit - not an owner). This is probably the path forward since one cooling system can be used all the time, whether riding or charging. Not much help for you, though.

ABSOLUTELY MINOR correction I wanted to just add here. The cooling loop for the motor/controller/AC charger is water/glycol. Basically antifreeze. There is a small bath of ATF that cools the gear reduction, so that's the only oil cooling on the bikes as it were. Other than that really solid info.

[DerKrawallkeks]

The Renault Zoe uses the inverter to charge. It's rare and it might be patented.

[GoneToPlaid]

Energicas have an oil cooling loop for the motor, controller, and now for the Experia the loop includes the AC charger. (as I understand it from reading about it a bit - not an owner). This is probably the path forward since one cooling system can be used all the time, whether riding or charging. Not much help for you, though.

ABSOLUTELY MINOR correction I wanted to just add here. The cooling loop for the motor/controller/AC charger is water/glycol. Basically antifreeze. There is a small bath of ATF that cools the gear reduction, so that's the only oil cooling on the bikes as it were. Other than that really solid info.

Thanks for the correction. I know I read somewhere about them using an oil cooling loop, so I was repeating BS. I just figured it was an eccentric choice to use oil, maybe for electrical insulation. Energica's equivalent of desmo valves.

The Renault Zoe uses the inverter to charge. It's rare and it might be patented.

Interesting. I found this about the Zoe power electronics:



I have to say, it is a lot more compact than my DSR's motor controller plus 4 TC chargers.

[GoneToPlaid]

MVetter, while I have your attention:

The TC chargers like used in your Diginow product are rated for an input voltage of 90 to 265 VAC (from the user manual). As they are switched-mode power supplies, it's at least possible they could work on a 250 VDC input as well. Do you know if this is feasible?

Would be neat to take a CCS station and tell it to output 250V, then step it down to Zero pack voltage with TC chargers.

Related - does anyone know of an open-source vehicle side implementation of the CCS protocol?

[MVetter]

They act as DC-DC converters and, as a rule of thumb, you can generally run double the rated AC input voltage. Generally. We did explode one at 400vdc input.

[GoneToPlaid]

They act as DC-DC converters and, as a rule of thumb, you can generally run double the rated AC input voltage. Generally. We did explode one at 400vdc input.

Thanks for confirming that. I'm sure you did the math, but for those following along: They're rated 265 VAC and that's RMS, so 265 * sqrt(2) is 375 V peak.