Upgrade to dual onboard chargers?

[Kandiru]

In the supercharger era the upgrade is only worth it if:

1. You are on call a lot and work hours are erratic, install a HPWC, but good luck
if you have a 200A grip and two air conditioners in your large home.

2. You live near or spend half-days near one of the rare 80A J1772 outlets.

In other words, unless you work erratic hours this upgrade is not for you.

Battery pack will also last longer if regularly charged at 30A vs 64A (20% of 80A).

PS: I installed the dual chargers in 2016, only made use of the feature once at a
hotel HPWC.

 

[Ostrichsak]

Battery pack will also last longer if regularly charged at 30A vs 64A (20% of 80A).

Got a citation to some supportive data for this claim? I see it mentioned occasionally when the conversation of 40A v 80A charging comes up but have yet to see any supportive data.

For a battery pack engineered to handle Supercharging of 400A+ @ 500v+ the difference between 30A & 64A @ 240v is negligible. Especially when you factor in that Tesla's (via Elon) latest stance on Supercharging is that it's affects on battery degradation are nominal. Other variables such as charge state storage will have a far more noticeable effect over time.

 

[GlmnAlyAirCar]

In the supercharger era the upgrade is only worth it if:

1. You are on call a lot and work hours are erratic, install a HPWC, but good luck
if you have a 200A grip and two air conditioners in your large home.

2. You live near or spend half-days near one of the rare 80A J1772 outlets.

In other words, unless you work erratic hours this upgrade is not for you.

Battery pack will also last longer if regularly charged at 30A vs 64A (20% of 80A).

PS: I installed the dual chargers in 2016, only made use of the feature once at a
hotel HPWC.

Also, as batteries age and lose capacity, the need to charge during the middle of the day increases, and 80A charging becomes more and more of a necessity. When I had my 70D, I found that, especially on weekends when I was doing a lot of driving, charge speed was a limiting factor in the middle of the day.

 

[vanwho]

It seems folks in the US have a different perspective on this, all good, but here is some context for Europe:

1. There are far fewer superchargers in the EU than US (has gotten better).
2. There are a ton of public and private free and paid "slow" AC charging spots all over cities and towns. Way more than the U.S. This is because the EU is all 240v 3-phase everywhere, easy installs. So these are all 22kw. At supermarkets and parking spots all over. Not too shabby.

22kw instead of 11kw is a huge difference for topping up, or grabbing something for the day or to get to the next SC, and not blow a bunch of time.

Also, used onboard chargers can now be had readily for $300-700.

For me, getting 22kw instead of 11kw at thousands of charging spots anywhere I go is definitely worth under $1000 (and many are free charging spots).

Hence I ask about the little details before I take apart too much (plenty of car repair experience down to rebuilding engines, electrical engineering, and software hacking - but I get this option isn't for everyone

Appreciate everyone's tips and experience.

 

[airborne spoon]

I installed a HPWC at my moms house for when i visit i can quickly charge up and have running around juice. it's one of the special edition signed elon ones, but i got it off facebook marketplace for $250, and i did the install for about $100 in parts.
Anyway charging at 80A is awesome 19kW is a sweet speed and can quickly charge me up. I've used plenty of destination chargers out in the wild and when i get stuck at one that only charges at 9kW its annoying to charge that slow.
My car came with dual chargers from tesla and i gotta say its totally awesome to have the ability to charge at 19kW.

 

[ucmndd]

Battery pack will also last longer if regularly charged at 30A vs 64A (20% of 80A).

lol, no.

 

[BrokerDon]

Our "inventory" 2015 P85D came with dual 40A chargers = 80A (19.2kW). Even with a 100A circuit / 80A Gen 1 Tesla HPWC I rarely charge at 80A since it really heats up our HPWC cable AND our Tesla's charge port... even after Tesla replaced our HPWC charge cable/plug. I lowered our nightly charge rate to 60A (14.4kW) and the cable & Tesla charge port run much cooler.

On road trips almost all public J1772 plugs are only 20A (4.8kW). Yes a few are 40A (9.6kW)... but I've never found one above 40A so our dual 40A chargers don't provide any benefit on the road.

Knowing what I know now, I wouldn't pay for dual chargers. It was almost free since we got a significant discount for buying an "inventory" car so no remorse... but I wouldn't add one or order them on a new Tesla.

 

[EV-Fixme]

Yes the load is supposed to be shared between both chargers.

Contrary to what we heard. Watching dual charger cars charge we see that the second charger is only used when charging above 40 amps. Not sure if there was a software change along the way. Or if we had incorrect information.

 

[BrokerDon]

Contrary to what we heard. Watching dual charger cars charge we see that the second charger is only used when charging above 40 amps. Not sure if there was a software change along the way. Or if we had incorrect information.

That's how it works on our 2015 P85D with dual chargers.

• charging rate <= 40A selected = only 1 charger is used
• charging rate > 40A charging is split equally between our dual chargers

You can watch this happen in our Tesla main display's charging screen when I set the charge rate to 80A. Charging amps ramps up from 0 to 40A... then pauses... then ramps up to 80A (when 2nd charger is powered up). This prevents the power spike that would happen if both chargers were brought online simultaneously.

 

[MooCow]

For some good reference info.

Google or search the web for Tesla SB-13-44-010
refer to :

https://static.nhtsa.gov/odi/tsbs/2016/SB-10081836-5448.pdf

 

[Silicon Desert]

Battery pack will also last longer if regularly charged at 30A vs 64A (20% of 80A).

Battery engineers at the factory say this is totally incorrect.