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Range Extender to Help Weak Lithium Electric Vehicles

From prime mover to a role as a range extender, the ICE engine is doomed to become a smaller part of future vehicle platforms.

Electric vehicles will force polluting engines to the background of society into range extender applications that bring out the best of engine spinning at 1 optimized RPM as a generator, as a range extender in electric motor vehicles.

More people in more places are becoming aware of air pollution because there are more people burning more things in more places. The problem, exhaust contaminating the air that everyone is breathing with tailpipe toxins that are not good for anyone.

Internal combustion engines are fraught with emissions problems from the exhaust created by tiny spark ignited explosions of gasoline mist compressed with atmospheric air sucked into the engine. Climate change from billions of engine emitting trillions of pounds of CO2, its the CO or carbon monoxide emitted by all the tailpipes near busy traffic corridors that gives rise to the health problems associated with the breathing of exhaust fumes. Oxides of Nitrogen or NOX along with fuel fumes, brake dust and tire dust, many vehicle emissions are toxic.

Electric vehicles address the tailpipe problems, especially when charged with renewable energy sources like hydro, wind, solar, geothermal, wave, hydrogen fusion, etc. The main problem with electric vehicles comes down to lithium ion battery deficiencies. The lithium rechargeable batteries used in the Tesla Model S for example are heat sensitive to anything hotter than 122 deg F and start to rapidly lose capacity from heat hotter than 150 deg F. This is why Tesla has to liquid cool its pack with an elaborate complex thermal management system, to keep the Panasonic tech. NCA chemistry cool enough to prolong the useful life of the large high capacity heavy low slung battery pack under every Tesla Model S or X!

Electric vehicles still produce brake dust & tire dust, as tires wear off the rubber becomes a nasty sticky black dust that mixes with oil from leaky car engines & transmission fluid from other leaky cars to form a toxic sludge. Brake pads also break down to form toxic dusts that mix with the tire dust and leaking fluids from other vehicles. If you talk to a person that operates a street cleaner about the stuff they suck up in their rigs and what it does if it gets on your skin, it would very obvious that roads are coated with toxic & pollutants from vehicles.

Regenerative braking in electric vehicles & most hybrid vehicles dramatically reduces brake pad/ rotor wear and reduces the emissions of brake dusts. This stems from the fact that regenerative braking slows the vehicle down by turning the electric motor into a generator to recharge the battery. The energy extracted from the drivetrain by the electric motor generator slows the vehicle down, meaning the mechanical brake pads and rotors are not used nearly as much as they would be in a conventional vehicle. One pedal driving exists as one of the coolest features of the Model S, its powerful regenerative braking making a backoff of the throttle slow the vehicle down fast enough that you barely ever have to press the brake pedal, especially not on highways when you have adaptive cruise control enabled through the autopilot setup.

Electric vehicles can produce more tire wear because of the instant torque. I leased a 2013 Nissan Leaf S for 24 months and the tire burning off the line acceleration was monster that eclipsed anything that even diesel engine vehicles could offer in terms of low end torque: amazing theme park ride instant electric torque! After 30mph the effect was minimized by a lack of higher RPM horsepower in the aforementioned LEAF.

The Tesla Model S on the other hand offers smile inducing performance from city to highway with high performance electric power that proved to the world that electric cars can be better than conventional gas powered vehicles. The Model S is known to chew up tires on account of its monster instant power delivery, though that depends on the users throttle input control. You can greatly extend the tire life of a Model S and reduce tire dust emission by driving  smooth & gentle like you are not in a hurry or trying to put a smile on your face by feeling G' forces..... ^^

Electric vehicles were once the most popular vehicle, around the year 1900 when more than 15000 Baker Electric "Phone Booth at 22mph" vehicles were operating in New York City, NY, USA. Early gasoline powered vehicles were loud, harsh, vibrating, hard to start with a hand crank and emitted noxious toxic stinky fumes. Wealthy people in the 1890's and early 1900's thought gasoline powered vehicles were too crude to be refined enough for their preferences. Once the electric starter motor made gasoline powered vehicles easier to start (around 1910"), their higher speeds and longer range on a tank of fuel meant time saved and in business time is money, something that means more to business people.

Electric Semi-trucks, the ones that haul food and stuff around for everyone, are making a comeback now because Tesla is once again showing the world that you can make a better truck if the engine is replaced by an AC electric motor! Electric motors are extremely energy efficient at up to 90% efficiency where even the best gasoline engines struggle to achieve 40%. This stems from the suck, squeeze bang blow cycle or 4 strong cycle common to almost all engine vehicles. In an engine about 1/3 of the gasolines energy is wasted heating the block, another 1/3 of the energy exits the engine as hot exhaust gas, & another 10% is lost as heat, friction, parasitic loads for AC/ Steering/ Brake pump assists etc & the alternator and loses in the drivetrain/ tranny/ shafts etc...leaving only about 30% of the gasoline energy available to move the wheels.

100% charging the mainstream lithium ion batteries of today causes rapid capacity fade loss that reduces the range of electric vehicles faster. 100% charging to full also shortens the calendar life of the lithium ion battery meaning electric vehicle batteries will wear out faster when regularly charged to 100%. Too hot, too cold, 100% charging, these things harm lithium ion batteries in your smartphone, laptop, tablet, electric vehicles and power tools. Keep lithium ion batteries partially charged about 50-60% when stored and operate them between 30-80% by only charging them for short intervals about 1/2 the time required for a full charge.

Not all lithium ion batteries are weak fade prone and dangerous like the higher energy density versions found in phones and electric cars today. Lithium Iron Phosphate or LiFEPO4 also called LFP, for example can be stored fully charged without harming it. LFP can last thousand of cycles and up to 10 years of regular use. I replaced the AGM starting battery in my Honda PCX150 with compact low mass Iron Phosphate X2 battery that never needs tender/ maintainer charging :) Similarly my solar powered wrist watches use 23 year life Lithium Titanate batteries. The reason these chemistries are not used in higher performance applications stems from the lower voltage and corresponding lower energy density. To give good run time on phones and good range in electric cars, the manufacturers always favor a less stable less durable but higher energy density chemistry like Lithium Cobalt Oxide : Hard Carbon : or Tesla Panasonic Lithium Nickel Cobalt Aluminum : Sintered Carbon Particle.

Reading about the $15,000 Alta Redshift MXR dirt bike with its 5.8kWh 18650 pack IP67 20G impact resistant liquid cooled design reminded me of why range extenders are needed to build compelling electric scooters and motorcycles. The 1.6 gallon (very small) gas tank in our Honda PCX has given me great pause for thought given the 85-105 MPG returned for a range of around 130-170mi per tank. The ACG 350w alternator starter in the PCX combines with a fuel injected 153cc single that makes 13hp & 11 lb*ft of torque through the belt CVT automatic for a max speed of 68MPH at 8800 RPMs. Honda recently announced an electric PCX for the Japanese Domestic Market or JDM : in Japan the lower range and slower speeds offered are sufficient to meet market demands of customers. In America where everything is all spread out really far apart unless you live in New York City, they need to make it highway safe with at least the same performance and range as the gas powered PCX I already own. At $3599 the gas powered PCX is going to make a hard price target for an electric version with similar range and top speed performance.

When driving the 13 Nissan Leaf S I was always wishing it had an onboard range extender like the BMW i3 REX. The 85miles of single charge range in that first gen LEAF could only be extended to ~123mi of range by going 16mph the entire time :) Going 70-90 MPH with full climate control power reduced the single charge range to 55-70 miles/ with a relatively new battery pack! Glad I leased that one. I kept it 30-80 charged almost the entire time I operated it, and it still lost 12% capacity after only 14,000 miles and 24 months. This is because Nissan used a somewhat fragile but very affordable and safe lithium chemistry called Manganese Spinel or Lithium Manganese IMR Laminate prismatic pouch a pack of 48 modules 2P2S etc. Leading Environmental Affordable Family or LEAF the engineers were forced to pick a safe affordable chemistry that is sadly known the world over to exhibit significant capacity fade in just a few years. That meant the initial 85 miles of average single charge range would steadily decline over time. Glad I leased the LEAF.

I dream of a day when electric vehicle batteries can last 50,000 charge cycles and 25 years of 100% fast charging all the time. I dream of a miracle battery chemistry that has better energy density than gasoline. I dream of a safe reliable battery chemistry that will enable amazing autonomous flying vehicles like the Ehang 184 to help more people in more places skip over toxic traffic corridors unhindered by ground traffic congestion, breaking free to cleaner air in electric VTOL autonomous passenger drone vehicles of all kinds :)

60 miles @ 55mph : A used Nissan Leaf can work for most people's daily commuting needs if they have access to other transportation options like a bus, motorcycle, scooter or car with longer range. An electric dirt/ motorcycle bikes needs about 2-4 hours of runtime for the battery to be equal to a 1.5 -4.0 gallon tank in an traditional engine powered bike.

Cars have a nice safety cell made of high strength steel with airbag and seat belts where motorbikes are exposed like a bicycle to weather and hazards. With less tire contact patch the 2 wheel vehicle is unsafe on wet roads, especially steel grates which are like ice when wet.

Cars are more stable, but they weigh more and are less fun to operate. The weather sealing warm climate controlled or cooled cabin of the car means you do not need to wear special gear like you do on a motorbike. I wear many layers for warmth & safety when operating the PCX150 on roadways in traffic etc. In fair weather I commute to work in the PCX instead of using our 24MPG 1993 Subaru Legacy L that we inherited from the late Papa Schwarz, Ken Drake the Drummer or Kenneth Schwarz my dad. The Subaru works fine and I am glad to have a fully depreciated vehicle to use in a low cost mode. The Subaru is a dirty burning inefficient vehicle with 190,000 miles that has lived outside exposed for most of its life and now. There is a small water ingress problem that humidifies the cabin subaru to a moisture saturation or Vapor Pressure condensate level where dew starts to condense on the inside of the windows. I am force to recirculate AC moisture stripped heater air to clear the windows and reduce cabin moisture. I am glad all the fabrics inside the subaru are petrochemical are not prone to molding like natural materials.

As battery technology improves, the weakness holding back better electric motorcycle will be lifting and awesome new products of unimaginable performance like electric drone bikes will become commonplace in the future. Today we have to live & cope with weak lithium ion batteries, but tomorrow we will move forward with better chemistry that makes life cleaner, safer and more enjoyable for everyone!

Keep thinking about it!

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