Geeky Questions

[james44]

Hi

My Outlander arrived this week. pleased so far, but mileage and environmental benefits seem somewhat dubious ... more on that when i have more data from extended usage.

In the meantime, some geeky questions I'd love to know answers to:

- Sometimes the energy flow diagram shows power from engine to wheels, with no arrow from battery. In that instance is it running 2WD?
- Can you make up your own spare 13A charging cable? with a 13A plug one end and a J1772 plug the other end? i.e does it really need that electronic box with the LEDs?
- Why do the 50kW fast DC chargers only fill the battery to 80% in half an hour? Surely they could deliver 50kWh in an hour and 25kWh in 30 mins. So filling the Outlander's 12kWh battery should be more like 15 to mins?
- When the engine does run, is this used to generate heat and drive an aircon unit as surely that's more efficient once the battery is depleted?

Any thoughts greatly received.

J

 

[maby]

Hi

My Outlander arrived this week. pleased so far, but mileage and environmental benefits seem somewhat dubious ... more on that when i have more data from extended usage.

In the meantime, some geeky questions I'd love to know answers to:

- Sometimes the energy flow diagram shows power from engine to wheels, with no arrow from battery. In that instance is it running 2WD?
- Can you make up your own spare 13A charging cable? with a 13A plug one end and a J1772 plug the other end? i.e does it really need that electronic box with the LEDs?
- Why do the 50kW fast DC chargers only fill the battery to 80% in half an hour? Surely they could deliver 50kWh in an hour and 25kWh in 30 mins. So filling the Outlander's 12kWh battery should be more like 15 to mins?
- When the engine does run, is this used to generate heat and drive an aircon unit as surely that's more efficient once the battery is depleted?

Any thoughts greatly received.

J

Hi there.

1. Number of wheels driven when the display only shows energy flow from engine to wheels - unclear - if the display is telling the truth, then you are correct - it is running in 2WD. Mitsubishi don't document this mode.

2. No, you can't make up a direct connect cable from the 13A socket to the car - the box generates the control signals that tell the car what it is connected to and what current it can draw.

3. The fast chargers are bypassing all the car's control systems and blasting power directly into the battery. I've never seen a good explanation of why it only goes to 80% but I guess it is to protect the battery. Also remember that the charging process is not linear - the rate of charge drops off as the battery gets close to full

4. The engine certainly is used to generate heat in preference to the battery if it is running - in fact it is the only source of heat on a GX3h. The aircon is always driven on electricity - if the battery is low, that electricity will be coming from the engine via the generator.

 

[ian4x4]

The Li Ion battery charges to 80% quite quickly, but as it is quite delicate at the higher voltages/temperatures, Constant Current / Constant Voltage Chargers are employed to handle this.

This last phase up to 100% has to be quite slow, to carefully control the battery voltage and temperature, incidentally the car battery will temporarily stop charging, what ever control you have selected, if it feels in danger of exceeding its parameters.
As I understand it Fast Chargers are not suitable for this, and anyway most people would not want this last very slow phase.

Earlier I wrote to a similar question;

On various articles on PHEV Li Ion car battery usage it states that the most efficient charge to retain in the battery (after initial EV stage) is between 20% and 35%.

The battery management system maintains this as it has been programmed by the car maker.

Also the same complex management system controls the mains charging cycle through it three stages;
A relatively quick Constant Current
then Transitional
And finally a quite slow Constant Voltage.

I think the complicated way in which this all works gives rise to the various confusing figures that appear in these forums.

You just have to trust Mitsubishi got it right

 

[maddogsetc]

Just to clear up your first question - the ICE can only ever 'drive' the front wheels - the rear can only be driven by the rear electric motor. So yes in the situation you describe it's a 2WD car. I'm sure this is clearly covered somewhere in Mitsubushi's documentation and I'm pretty certain it's covered in the official videos on Youtube & the MM website as well.

 

[james44]

Many thanks for the helpful replies

- I had hoped to make up a cheap spare 13A cable as replacements seem to be £385 which as lot for what it is. Long story ... the tethered 16A option doesn't work at home due to where consumer unit is and where the car is parked on drive, so I use the cable daily at home and am a bit worried about theft. I hoped the car would default to 13A max in the absence of a signal that says anything else.

- Understand the rate of charge issue with fast chargers. Tried out the 50kW charger today, got to 80% in about 17 mins, it then shut off. I restarted it and it went to 95% in the next 10mins. So you do wonder why it doesn't just continue at a lower rate after 80%?

One more anorak question

I understand there's no gearbox and above 75mph the ICE directly engages the front wheels at a constant ratio. How then does the ICE couple with the front wheels at rapid acceleration at very slow speed, wouldn't that need a different ratio?

Thanks again!

J

 

[jaapv]

I would be careful with overcharging tricks like that. They will certainly shorten battery life. Even frequent fast charging will do that. You can find the warning in the manual.
The ICE does not couple with the wheels at low speeds, the car goes into series hybrid mode for extra power.

 

[maddogsetc]

ICE can drive the front wheels directly from about 45mph but the car will default to EV mode at speeds up to about 75mph until the battery is depleted or Save / Charge are engaged.

When more torque is needed than ICE can provide alone ie. accelerating from (or, on uphill sections, at) lower speeds the car can supplement ICE with the electric motors as required.

Above 75mph ICE will always drive the car directly as the electric motors cannot drive the wheels at these speeds.

 

[user 422]

ICE can drive the front wheels directly from about 45mph but the car will default to EV mode at speeds up to about 75mph until the battery is depleted or Save / Charge are engaged.

When more torque is needed than ICE can provide alone ie. accelerating from (or, on uphill sections, at) lower speeds the car can supplement ICE with the electric motors as required.

Above 75mph ICE will always drive the car directly as the electric motors cannot drive the wheels at these speeds.

Your are forgetting that the PHEV is PRIMARILY an Electric Drive system - the electric motors are permanently attached their relevant axles and its not true that ONLY the "ICE" drives above 75mph. above 45mph the ICE clutch can engage so that the Engine power is transmitted to the front wheels - but it is by no means a permanent situation - I have seen ( flow diagram ) and can hear engine RPM changes depending on what the System controller demands...

 

[jaapv]

Indeed and when the car is in parallel mode (i.e. with the clutch coupling the ICE generating unit to the front wheels ) there is still electric power on the rear and front wheels to maintain stability. The car is essentially powered electrically and will always operate as an electrical 4wd with occasional ICE assist at higher speeds.(bar highly exceptional circumstances that is emergency power mode.)