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My New (to me) 2013 Chevy Volt

Acquisition

Once I decided to put the truck up for sale, I started looking at the used electric and hybrid car market to see what the price ranges and availability were.  I have always liked the concept GM used in designing the Chevy Volt.  It is a true plug-in electric car which has an engine/generator to take over when the electric range is used up.  It always drives as an electric vehicle, the power source just varies between the batteries and the generator.  The Nissan Leaf is an all electric car with around 100 miles of range, but when that is exhausted, you stop!  The Prius had come out with a plug-in version of their hybrid, but the electric-only range was just 7 or 8 miles, although their newest version, the Prime has about 25.  As a comparison, my truck was calculated to have a 40 mile range, but in reality, in hilly Prescott, it had only about 25 to 30 miles.

I quickly narrowed the field down to the Chevy Volt, and as I studied it more closely, I found out that it is much more complicated than just an electric car with a backup generator.  It has a highly engineered system of two motors, one of which can also be used as a generator, a “transmission” which can connect the various components in different combinations to provide the car with the highest efficiency at a number of different combinations of speed, power needed, uphill/downhill, etc.  For the generation 1 Volt (model years 2011 through 2015) the electric-only range is typically 35 to 40 miles and the gasoline engine will yield from 35 to 40+ miles per gallon.  With a 9.3 gallon fuel tank, this gives the car a typical range of about 360 miles.

I started logging all the Volts I found in advertisements by price, year, features, and special conditions listed.  I talked to our local Chevrolet dealer about the Volts and asked them to let me know if they found any good ones.  After I sold the truck, but before it was picked up (payment and paperwork were complete), I decided to stop by the dealer on my way home from being out most of the day.  The salesman asked if I got his message, and I explained that I had been out and no, I had not.  He had called to tell me they had a 2013 Silver Volt with under 26,000 miles that just came out of the certification process in the shop, and was now available for sale.  In discussing the details I realized that there were only 3 cars on my list that were less expensive than the asking price of this car.  Two of them were rebuilt wrecks with salvage titles, and the 3rd was just a few dollars less and had over 40,000 miles –all were in the Phoenix area, about a 2 hour drive. 

This car has the “Safety Package #1” which I really wanted, as it was the only way to buy a factory backup camera.  It also provided an auto-dimming rear view mirror and ultrasonic alarms while backing up warning if you get close to anything.  The other "package" on this car is the Comfort Package including heated front seats and a leather wrapped steering wheel.

To make a long story short, by the time I arrived home that night for good, I owned the Volt.  I had to make a couple trips home during the course of the negotiations, one with the salesman driving my Jeep to get it home, and for me to get on my computer to transfer some money, and then another solo run to pick up my trust documents. Of course I drove the Volt for these round trips of about a dozen miles each.  Since I had promised the truck buyer I would keep the truck garaged until he could pick it up, the Volt got the Jeep’s spot in the garage, and the Jeep spent the night out.  That lasted only one night, as the truck was picked up the next day.  The buyer of my truck is also the owner of a 2013 Volt he purchased new.

 

And here is my 2013 Chevy Volt  (my truck is in the garage for its final night)


Features

The Volt is a very high-tech car.  Pretty much everything in the car is computer controlled.  The instrument and radio/HVAC panels are each 7 inch LCD display panels.  Most of the radio and comfort controls, besides being touch sensitive on the display, have touch sensitive buttons on the panel below the display.  It contains all the latest electronics such as Bluetooth for both music listening and hands free cell phone use, Homelink garage door openers, keyless entry and driving where if your keys are on your person, you can unlock the doors and press a button to run.


The main "Instrument Panel" screen contains the speedometer, icons for estimated battery  range remaining,
estimated gasoline range remaining, all the normal warning icons, and an area under the speedometer which
displays warning and notifications.  You can also select items to display here such as tire pressure, % oil life
remaining, primary and trip odometers, showing both electric and gas stats.  There is also a rotating ball which is
really an accelerometer, to help drive efficiently.  Optionally you can switch this for a larger gas pump icon.  If the
 engine starts and supplies you power, it swaps places with the battery symbol and turns green.  You always can
tell at a glance  which power source you are using, as it is often not obvious when the engine starts.



The Entertainment / Comfort display has about a dozen different screens for different purposes.  
The main ones are the radio controls, and the heating / cooling controls.  It also has several screens for
 power flow and power usage.  All the items below the display with small bumps are touch sensitive areas
 for directly activating functions which can be activated using the touch screen display.


Driving the car is a total pleasure!  To start it, you get into the car with the keys in your pocket, touch the start button and it comes alive.  The main display lights up with all the icons showing initially, then it goes to a functional display, where only the active items are shown.  The center console also starts, beginning with a Volt logo while the computer starts up.  It then displays which ever display was last on.  The parking brake is electric.  It took me a little time to get used to that.  There is a tab on the console which if you press it forward, releases the brake.  To set the brake, you pull the tab out.  I had a problem initially remembering which was which, until I related it to a conventional brake handle.  Back is on, forward is off!  Problem solved.

I was initially annoyed by the ultrasonic back up sensors, as they would see the wall next to the garage door and beep as I backed out until the rear bumper cleared the door opening.  Now I am used to it and it is only for a few seconds, so it really does not bother me now.  The backup camera is one of the car's weak spots.  The picture is grainy and of too high a contrast, but is satisfactory for now.

Once out in the street, stepping hard on the "gas" really pushes me back into the seat.  The low end torque is fantastic!  Electric motors have maximum torque at zero RPM, very unlike an internal combustion engine
(ICE), or as my dad used to say "infernal combustion engine" - he was a steam power enthusiast!  Driving on a smooth road is almost totally silent.  Of course most of the roads are not that smooth, so you hear the normal road noises, but that's about all.  I love driving this car!

Driving Modes

As you drive, you can select any of 4 different modes:  Normal, Sport, Mountain, or Hold.  

Normal mode sets the car's parameters to average values for general driving.  

Sport mode makes the car seem much more responsive.  I don't think you actually have better performance, it just makes the throttle give you more power with less travel.  I believe that if you "mash" the throttle in Normal mode, you get the same as if you do the same in Sport mode.  I may be wrong.

Mountain mode leaves more battery reserve for better performance in climbing grades.  It allows the battery to discharge to only about 45% of its normal range, then starts the engine.  The engine keeps the battery at about the 45% level then shuts off, cycling as needed to maintain this level.  This assures adequate battery power will always be available for the steepest, longest grade in the United States.  This is the only mode where the engine actually increases the SOC of the battery.  If you enter Mountain mode with less than 45% battery remaining, it will gradually increase it to the 45% level.  At all other times, the engine will only charge the battery back to the level it was to replenish the energy used to supplement the engine's output.

Hold mode will maintain whatever level of battery you have when you enter Hold mode.  This allows you to use the engine for freeway driving, where the engine is very efficient, leaving your battery for city driving when you arrive at your destination.  If you were to make the drive in Normal mode, the first part of the trip would discharge the battery, then the rest would be with the range extending engine.

Batteries

There are two sets of batteries in this car, the typical 12 volt battery which powers the lights, radio, power windows, etc., and the traction battery.  

The 12 volt battery is a maintenance free AGM (absorbed glass mat) battery which powers all the electronics and computer systems in the car in addition to the lights, and other accessories typical of the ICE powered cars.  The main item it doe NOT power, is a starting motor.  More on that below.

The traction battery is where all the magic originates.  It is a 360 volt, 16.5 killowatt hour lithium ion battery.  This battery of course powers the main drive motors of the car, but it also supplies power for the heater and the air conditioning.  Using one of the two driving motors, it also starts the IC engine - there is no starter motor per se on this engine. There was an immense amount of engineering involved in designing the battery for this car.  One of the main driving forces behind this effort was to assure that the battery has a very long life.  The primary things which shorten the life of this type of battery are temperature, either too hot or too cold, charging to and operating from too high a level of charge, and discharging the battery to too low a level.

To assure the maximum life, the engineers designed a liquid cooling and heating system for the battery.  The battery is held to a fairly narrow band of operating temperatures, with an electric heater, powered by the traction battery, to warm it when needed, and the main air conditioning system is used to cool it as required.  Also the operating range is restricted to about 65% of the battery's actual capacity, so the working capacity is about 10.5 kWh.  When the driver sees that the battery is all the way discharged, there really is still 22% charge left, but he cannot use power from this range.*  By the same token, when the battery is fully charged, it is really at about an 87% level.  These steps have been very successful at maintaining nearly full capacity on even the earliest Volt batteries with very high mileages on them.

*There is one exception to the minimum operating level of 22%.  If the vehicle is at 0 charge (22% actual) and it runs out of fuel, an emergency mode activates which limits the car to "reduced power" and will allow the battery to be used until it discharges to an absolute minimum of 15% of actual battery capacity.  This allows several additional miles of low performance driving to hopefully allow making it to a gas station.



This is an example of the main traction battery from a Volt.  The insulated, protective cover on the
left has been removed.  (There is a second complete Volt battery still in its cover under the top cover.)  
In operation, the battery is located under the floor of the car, with the main left hand portion located
 under the center arm rests, and the cross portion on the end, under the rear seats.

These batteries belong to a friend whom I met when he bought my electric truck from me.  He purchased
these two batteries from a salvage yard shortly thereafter.  These batteries are destined to to be disassembled
 and installed in the truck as its future source of power.


Charging the Batteries

To charge the traction battery of the Volt, an accessory known as an EVSE, (Electric Vehicle Supply Equipment) is used.  This is a device which plugs into the main AC supply and provides a cord and a special connector to plug into the car when the battery needs charging.  Many people erroneously call these chargers, but the charger is built into the car.  This device is only a safety interface to plug in the car.  The special connector has 5 pins.  Two of the pins are the actual AC power to supply the charging current to the charger in the car.  One pin is a ground wire.  The other two pins are a special communication link between the EVSE and the car to allow them to negotiate the proper current and voltage.  Only then is power actually supplied to the two power pins.  This way, the driver is never holding a connector with high voltage at the connector, and it is safe to use even in a driving rain storm.  It must be fully plugged into the car before power is applied.

 
On the left the charging connector is plugged into the car.  The charge port is on the right.  The top 2 large
pins transfer the AC current to charge the car. The center bottom pin is the ground connection.  The two smaller
pins are shorter than the others to insure that the power connections are made before the negotiation for the
 charging rate can begin.  There is absolutely no AC power on the connector until the connector is securely fastened in  place.


The volt can use two types of EVSEs, a Level 1 and a Level 2.  The EVSE which comes with the car is a Level 1, and uses only standard 115 volt power.  If the outlet is a dedicated outlet, the owner can set the car to charge at 12 amps.  If the outlet is shared with other loads, the default setting for the car is to charge at 8 amps.  A level 2 charger operates from 230 volt power and can charge the car at up to 15 amps.

To charge a fully depleted (22% SOC) battery with a Level 1 EVSE at 8 amps takes about 15 hours, and at 12 amps about 10 hours.  A Level 2 EVSE will charge a fully depleted battery in about 4 hours.  Of course normally the charge times are less as the battery is not usually fully depleted each day.

Until I think of something else, this pretty well describes the main elements of this fine car.

Dick