EVSE charging at home.

[JoulesThief]

I drive conservatively, usually 60 mph on freeway, and probably 40-50% of my drives are at 35 to 45 mph speed of traffic on Blvds. Last full recharge, I averaged 5.6 mile per kwh on the infotainment center.

Currently charging and with 241V showing... I am charging at 30 amps at a 7.2kwh rate. I plugged in at 9:10 am, and when I took a reading on car-net at 10:12 am I went from a range of 22 miles left with no ancillary stuff running in the backround to 65 miles of range showing on my Car-Net App. Adding 43 miles per hour to me... seems extrordinarily high?

When I was first using public chargers the first month of ownership, same routes driven, I was adding 32 to 33 miles per hour most of the time, on what ever was coming out at 30 amps times the voltage... and seeing 5.5 miles per kw on the infotainment system then.

Kind of makes me wonder if an option ever came out to add a charger on board that would handle 40 amps at 240V, how fast would the e-Golf charge then, a full 33% faster still?

 

[miimura]

I drive conservatively, usually 60 mph on freeway, and probably 40-50% of my drives are at 35 to 45 mph speed of traffic on Blvds. Last full recharge, I averaged 5.6 mile per kwh on the infotainment center.

Currently charging and with 241V showing... I am charging at 30 amps at a 7.2kwh rate. I plugged in at 9:10 am, and when I took a reading on car-net at 10:12 am I went from a range of 22 miles left with no ancillary stuff running in the backround to 65 miles of range showing on my Car-Net App. Adding 43 miles per hour to me... seems extrordinarily high?

When I was first using public chargers the first month of ownership, same routes driven, I was adding 32 to 33 miles per hour most of the time, on what ever was coming out at 30 amps times the voltage... and seeing 5.5 miles per kw on the infotainment system then.

Kind of makes me wonder if an option ever came out to add a charger on board that would handle 40 amps at 240V, how fast would the e-Golf charge then, a full 33% faster still?

Public chargers are usually on commercial 3-phase power supplies, so they only give 208VAC nominal. They frequently sag to around 200VAC. Your house is delivering 241VAC, so that's 20% more power right there. Charging MPH is deceiving because it is factoring in your driving efficiency.

Of course, a 40A on-board charger would charge 1/3 faster. However, the faster you charge the battery, the more likely it will slow down as the battery gets full. The RAV4 EV has a 40A charger and slows down from 9.6kW to about 5kW as it gets full. I have never used a energy monitor on the e-Golf's EVSE to see if there is any charge tapering.

 

[JoulesThief]

I drive conservatively, usually 60 mph on freeway, and probably 40-50% of my drives are at 35 to 45 mph speed of traffic on Blvds. Last full recharge, I averaged 5.6 mile per kwh on the infotainment center.

Currently charging and with 241V showing... I am charging at 30 amps at a 7.2kwh rate. I plugged in at 9:10 am, and when I took a reading on car-net at 10:12 am I went from a range of 22 miles left with no ancillary stuff running in the backround to 65 miles of range showing on my Car-Net App. Adding 43 miles per hour to me... seems extrordinarily high?

When I was first using public chargers the first month of ownership, same routes driven, I was adding 32 to 33 miles per hour most of the time, on what ever was coming out at 30 amps times the voltage... and seeing 5.5 miles per kw on the infotainment system then.

Kind of makes me wonder if an option ever came out to add a charger on board that would handle 40 amps at 240V, how fast would the e-Golf charge then, a full 33% faster still?

Public chargers are usually on commercial 3-phase power supplies, so they only give 208VAC nominal. They frequently sag to around 200VAC. Your house is delivering 241VAC, so that's 20% more power right there. Charging MPH is deceiving because it is factoring in your driving efficiency.

Of course, a 40A on-board charger would charge 1/3 faster. However, the faster you charge the battery, the more likely it will slow down as the battery gets full. The RAV4 EV has a 40A charger and slows down from 9.6kW to about 5kW as it gets full. I have never used a energy monitor on the e-Golf's EVSE to see if there is any charge tapering.

It shows quite clearly that the Amps taper off the last 20 to 25 minutes on my JuiceBox40 Pro application on my Android based phone. The last stage is only at 4 amps... it just keeps stepping down, probably some sort of algorithm on board the e-Golfs charger packs that dials things back with the pilot meter value and a resistance value?

I show 14.79 kw added from 9:10 AM to 11.22 AM and range went from 22 miles to 111 miles showing on car-net. 89 miles added in 2 hours and 10 minutes. I would probably show a full 129 to 130 miles of range if I topped off the charge on the battery.

 

[miimura]

It shows quite clearly that the Amps taper off the last 20 to 25 minutes on my JuiceBox40 Pro application on my Android based phone. The last stage is only at 4 amps... it just keeps stepping down, probably some sort of algorithm on board the e-Golfs charger packs that dials things back with the pilot meter value and a resistance value?

The on-board charger does what it needs to, coordinating with the battery management system. It is getting the same pilot signal from the EVSE the whole time. The pilot only indicates the maximum the car is allowed to take from the EVSE, not how much it has to take. I don't know what resistance value you might be talking about.

I show 14.79 kw added from 9:10 AM to 11.22 AM and range went from 22 miles to 111 miles showing on car-net. 89 miles added in 2 hours and 10 minutes. I would probably show a full 129 to 130 miles of range if I topped off the charge on the battery.

What level did you charge the battery to when it showed 111 miles? If you charged the car to 100%, why would it ever show more range unless you drove it again with a higher efficiency? Also, the manual says not to start charging if the battery is above 98%.

 

[JoulesThief]

It shows quite clearly that the Amps taper off the last 20 to 25 minutes on my JuiceBox40 Pro application on my Android based phone. The last stage is only at 4 amps... it just keeps stepping down, probably some sort of algorithm on board the e-Golfs charger packs that dials things back with the pilot meter value and a resistance value?

The on-board charger does what it needs to, coordinating with the battery management system. It is getting the same pilot signal from the EVSE the whole time. The pilot only indicates the maximum the car is allowed to take from the EVSE, not how much it has to take. I don't know what resistance value you might be talking about.

I show 14.79 kw added from 9:10 AM to 11.22 AM and range went from 22 miles to 111 miles showing on car-net. 89 miles added in 2 hours and 10 minutes. I would probably show a full 129 to 130 miles of range if I topped off the charge on the battery.

What level did you charge the battery to when it showed 111 miles? If you charged the car to 100%, why would it ever show more range unless you drove it again with a higher efficiency? Also, the manual says not to start charging if the battery is above 98%.

It's exactly 1.5 ticks from full on the battery level of charge gauge. No intent on starting another charge, I figured I am probably at 85% SOC, will run battery down again quite a ways before attempting another recharge. I usually attempt to only get a full recharge every 3 or 4 recharges, and then I recharge fully only just before I am about to leave, so the battery doesn't sit for any length of time at fully charged.

 

[RonDawg]

Kind of makes me wonder if an option ever came out to add a charger on board that would handle 40 amps at 240V, how fast would the e-Golf charge then, a full 33% faster still?

With just 24kWH of battery, the additional costs from both the manufacturer's and homeowners perspectives are probably not worth it. Assuming the car uses all 24 kWH of battery (it doesn't) and 100% charging efficiency (which you will never get) I calculated that going to a full 9.6 kW (240 volts x 40 amps) only speeds up charging time by 35 minutes. If VW limits the draw from the battery to 21kWH (like Nissan does with the Leaf), the difference in charging time is less than 45 minutes, again assuming every watt pulled from the wall goes into the battery.

Most EV owners/lessees primarily charge at home, so a 1/2 hour off the total charging speed isn't going to be worth the electrical upgrades most middle-class homes would require to handle a dedicated 50 amp circuit. The faster speed would be beneficial at a public charging station so you can get to your destination sooner (and free up a charging station quicker), but as mentioned above you're lucky if you even get 7.2 kW from them.

Teslas do have the ability to charge this fast on L2 but then they have considerably larger batteries.

 

[JoulesThief]

With just 24kWH of battery, the additional costs from both the manufacturer's and homeowners perspectives are probably not worth it. Assuming the car uses all 24 kWH of battery (it doesn't) and 100% charging efficiency (which you will never get) I calculated that going to a full 9.6 kW (240 volts x 40 amps) only speeds up charging time by 35 minutes. Most EV owners/lessees primarily charge at home, so a 1/2 hour off the total charging speed isn't going to be worth the electrical upgrades most middle-class homes would require to handle a dedicated 50 amp circuit. The faster speed would be beneficial at a public charging station so you can get to your destination sooner (and free up a charging station quicker), but as mentioned above you're lucky if you even get 7.2 kW from them.

Teslas do have the ability to charge this fast on L2 but then they have considerably larger batteries.

EVSE was wired for 50 amps, 50 amp breaker, 40 amp continuous with a 14-50 NEMA and a compatible JuiceBox 40 Pro. Maybe the next electrical car I buy can run 40 amps continuous charging, due to larger charger pack and larger battery, say 30 or 36 kw instead of 24?