[Flex]

http://www.cleanfleetreport.com/tech-hybrid-driving-techniques-max-mpg/

 

[FlNiro]

It's a pretty good article. When they talk about getting to know the gauges they should also caution that you shouldn't get too caught up in the gauges, still have to worry about driving the car. Best advise the article gives is to accelerate smartly up to speed or a few mph. over what you want and then back off the throttle a little to get it to kick into EV mode.

 

[yticolev]

Wow, totally disagree with that article about EV use. Maximizing EV use at low speeds in the city gives you the best bang. Trying to get your car to flip into EV on the highway is a fun game, but in practice, a zero sum game for added mpg. Let the BMS, well, manage the battery use on the road. The BMS will keep the battery in a middle range, and it doesn't matter if it is adding torque to the ICE or actually in EV for short periods. Same motive force.

 

[Roadkill401]

I'm with yticolev, and disagree with the article on startup. The idea of sort of gunning it to use the engine to accelerate from a full stop is just simply out there. I know from my Edge that is not a light crossover, that from the standstill it takes a huge amount of fuel to get the car going, but I can easily get into the 40-50mpg fuel use range when coasting at city driving speeds. It makes much more sense to let the battery take the hit and power the electric motor to get the car initially going. They don't use small AA batteries inside these cars, the traction battery is quite large and you won't drain it just by letting the electric motor do the work to start you moving. As well, if you think of it, the idea of regenerative braking is that you recapture the momentum energy when you slow down and stop at the next set of lights. That system is at least 70-80% efficient, so the next time you slow down and stop you are topping back up the battery to use when you start next.


One thing that I have heard is that your hybrid system likes to keep the battery charge at or around the 50-60% mark. This is good for the battery as it will make it last a whole lot longer. I have some of those EGO electric yard tools with the 56v lithium batteries. The by design will discharge themselves to the 50% mark if you don't use them for a period of about 2-3 weeks. I had a good chat with one of the engineers who explained why and his suggestion was when you will extend the life of the battery if you top up charge it about 1 hour before you use the tool to about 75% and don't run the battery down below the 20% mark. These are effectively the same type of battery inside the Niro.


With that knowledge, you shouldn't really play games to try and get the battery level indicator inside the car to get up high as it will defeat what the logic electronics inside the car are trying to do. When driving on a flat at speed, the processor brains inside the car can decide to run the engine at the magical 1800-2000rpm that gives the least wear to the motor and gets the most fuel efficiency out of it. It will direct some of the power to the wheels and the rest over to topping up the battery. If the engine is getting that 50-60mpg efficiency, then why would you mind? The last thing I want it to force the engine to have to rev up and be in the 3-6mpg range even if it's for only 15-20 seconds as that will use far more fuel than it running for 2 minutes at cruising speed with 50-60mpg efficiency.

 

[picstart]

It is useful to note that Lithium is the lightest and most abundant metal in the Universe ( created in the big bang). It is used for the energy ( 3.7-4.2) volts its ion has. It is next best to Hydrogen ions (13.6v by comparison). The Niro batteries only have the name lithium in common with most other Lithium batteries. What most differentiates lithium batteries are their anodes, cathodes and electrolyte. EV car batteries have little in common with most lithium batteries ( ex cell phone etc). It is the anodes cathodes and electrolyte that give them the property of charge/discharge rates, number of charges,self discharge rate and charge density. Early EV's may have used a multi purposed battery ( early Tesla) but today the anode cathode and electrolyte technology tailors them to the needs of the car. Lithium gets you the electron drop from ionization to the second shell ( 3.7v). It's a shame hydrogen is a gas and only available for fuel cell storage. Advances in cathode anode and electrolyte research is increasing lithium charge density and most important faster charge rates.

 

[brandent]

It's a pretty good article. When they talk about getting to know the gauges they should also caution that you shouldn't get too caught up in the gauges, still have to worry about driving the car. Best advise the article gives is to accelerate smartly up to speed or a few mph. over what you want and then back off the throttle a little to get it to kick into EV mode.

That's not how physics works. 'Accelerate quickly to save energy' is massively off base as to what burns energy. the rest of the advice amounts to 'don't drive it like you stole it' with a touch of 'you're too dumb to understand air resistance goes up dramatically as you drive faster'.

And then he contradicts himself. Right after telling us hard acceleration is the key, he says use ECO mode because it'll reduce acceleration.

 

[yticolev]

There is a bit of truth in what he says. The engine gets really poor mpg below 30 mph (look at the instant figures), so getting there efficiently does pay off in less time below 30 mph. Moderate acceleration is best, but typically we have to do that anyway due to traffic. I double check mode when there is no traffic, and if the engine is already running after I take off from a start, I accelerate moderately. If in EV mode in town, I will accelerate super slow so the engine doesn't turn on in town at speeds lower than 30.