Electric vehicles

TLT Sounding Board September 2020

 



Executive Summary

Electric vehicles (EVs) have been a hot topic for discussion. TLT readers believe there are many problems, especially tribological, that still need to be addressed. One issue mentioned by readers is developing infrastructure for charging vehicles. Another common problem is battery maintenance and disposal. “I worry about the materials used for battery manufacturing and the ability to recycle those materials,” one reader said. “Globally, no battery should be manufactured unless there is the capability to recycle the materials with enhancements.” TLT readers also are divided when asked about when EVs will exceed the number of internal combustion engine (ICE) vehicles.
 
Q.1 What are the biggest tribological issues that need to be addressed as electric cars continue to develop?

Bearing lubrication.

Battery technology, rapid charge systems and building the infrastructure to provide charging systems across the country and the world.

Decline in the use of lubricants. Other equipment will continue to use them, but automobile use will greatly decline.

There are two issues in play that affect potential tribological issues: (1.) The wiring and movement of the metal parts from engines with electrical power sources and (2.) the friction caused on the wearing of the engine pistons and block.

Lower viscosity transmission and drivetrain fluids to lower overall drag and assist with extending battery life.

Drivetrain lubrication requirements.

Heat issues generated by electric engine components during peak usage and rapid shutdown. Will sealed electric systems be lubricated for life? Will they be fluid lubricated or use very light base oil greases? Which synthetics are most likely? How does hybridization fit into the mix?

Oil compatibility with electric and magnetic fields. Fire hazard due to static electricity discharge inside oil system, particularly in the event of a car accident.

Compatibility with materials of construction.

Noise, or the lack thereof.

Magnetic bearing.

Thermal transfer, power efficiency.

Low viscosities while providing adequate protection for long intervals.

The replacement of a single electrical motor with gearbox transmission by the direct use of electrical motors in each wheel. 

Gears and bearing parts protection at high motor speeds, coolant/gear fluid flow at low temperatures for efficiency and lubricant cost with more exotic base oils selected possibly for cooling capacity.

(1.) New chemical formulations, specifically for electric machines. (2.) Dealing with electrical discharge across any mechanical interfaces.

Grease development to cover needs.

As petroleum use decreases, costs might increase for ICE vehicles.

Developing infrastructure for charging vehicles, training repair shops for working on high-voltage vehicles, changes in how the units are recycled and battery replacement. Changing battery technology, lubricants with high dielectric strength. Lubricating of wheel bearing and other moving components.

As the electric power and travel distances increase in new vehicles, there needs to be a discussion on cooling with fluids, glycol or oil based. Electric motors on construction equipment are already using fluid cooling. However, there is little discussion on how to properly monitor fluid condition for these applications.

High-temperature greases that will stay in place.

Friction reduction on all wheels.

Low friction and low-noise bearing greases and synthetic gear oils.

Friction reduction and modulation, energy consumption, energy efficiency.

For transitioning from ICEs to EVs: (1.) New seals with high efficiencies have to be developed. (2.) New greases that help in lowering friction between electric motor and transmissions, in steering systems, tires, wheel bearings and flywheels, have to be developed and suitably assessed for their performance. (3.) More efficient electric motors need to be developed—meaning the friction during power generation and transmission has to be lowered.

Battery coolant should act as a lubricant in as many moving parts as possible. Water-based coolants are nearly three times more effective in energy dissipation than oil-based fluids. However, aqueous lubricants cannot assure adequate wear protection and low coefficient of friction. Lack of understanding in water-mediated tribofilm formation is preventing the development of well-performing, waterbased battery coolants.

On these issues we must take into account that the lubricant molecule can be affected by electric or static current and how a lubricant should resist this phenomenon.

There aren’t any major tribological issues to address. The overall quality of base oils will be key. Transformer quality oil will be more common. Driveline and secondary lubrication (door locks, hinges, etc.) are already available.

Q.2 What unintended consequences, positive or negative, do you foresee as the marketplace transitions to electric vehicles?

Electrical grid charging stations.

Grid disruptions and battery failure implications, such as fires or reduced charge capability over the long haul.

I worry about the materials used for battery manufacturing and the ability to recycle those materials. Globally, no battery should be manufactured unless there is the capability to recycle the materials with enhancements.

Battery maintenance and disposal is going to create a large environmental issue as more EVs hit the marketplace. I also am extremely worried about companies pushing autonomous technology through to customers that has not been properly vetted. Tesla has seeded into the public mind that EVs are automatically associated with autonomous driving technology, and we have already seen concerted efforts by their leadership to over-exaggerate the autonomous capabilities while simultaneously downplaying documented cases of fatalities caused by faulty technology.

The hydrocarbon economy is huge. Many jobs will be lost, and economies will be altered.  Inability of the electrical grid to cope with the increased demand. Improvements will need to be made quickly to keep up with huge investment. Who is paying for this? Who is planning for this, or will it just be a reaction?

Decline of oil and gas industry.

Hopefully harmful emissions will decrease, but perhaps the limited range of EVs and requisite charging times will force people to plan trips a little better (fewer short trips for one purpose, more carpooling, etc.).

Mileage tax for all cars. Gas and diesel are taxed. How is the EV going to participate? Will all vehicles have to report mileage?

Aggravated people parking cars at charging stations. What now? You cannot carry an extra five gallons of electricity with you?

I see that the movement to EVs will cause a different set of issues regarding movement of mechanical/steel parts. The fuel/air ratio in combustible cars creates energy and heat while the electrical will create more friction and other issues as they are pushed differently.

Negative effect with the decrease in engine oil purchases. Oil suppliers will need to be nimble as technologies rapidly evolve.

When do you think the number of EVs (including hybrids) will exceed the number of ICE-powered vehicles worldwide?
Five to 10 years 9%
11-20 years 34%
21-30 years 28%
More than 30 years 21%
It’ll never happen 8%
Based on responses sent to 15,000 TLT readers.

Limited charging stations and the time needed to recharge, plus how to charge the consumer directly for the amount of electricity used. How will the government track and tax usage for tax purposes? Will the government add additional taxes to homeowners to cover the electric cars? Will the government revert to taxing tires instead of fuel?

The service industry will have to fulfill dual functions for the foreseeable future. Staffing these shops with trained technicians will be very challenging.

When EVs become old after many years of usage, what will be the most vulnerable area for vehicle maintenance and driver safety?

The shortage of electric charging stations being available.

E-waste disposal of batteries after use.

Infrastructure requirements.

New materials to extend the life of a battery (service life and storage ability), and new materials needed for the construction of vehicles could lead to environmental issues.

The strain on the electric grid. The grid can barely handle a heat wave in the summer and everyone turning on air conditioning. Imagine every car on the road being placed on the grid. Add to that, the closure or anticipated closure of nuclear and coal generation plants, it will be a challenge to keep capacity up with demand.

Larger life cycle cost and environmental impact.

The disappearance of lubricants for automotive use implies a profound transformation of the lubricant industry and the supply and service chain, with a significant loss of jobs in retail sales and the closing of mechanical workshops that cannot change technology.

Market disruption to gasoline producers, increased demand for rare metals, fewer sources of free trade for rare metals, people running out of juice on the road before they reach a charging station.

Increased scuffing of elements, increase in temperature and wear in friction contacts.

Lack of battery recycling.

No road taxes to cover wear and tear on highways.

Over-crowded charging stations along the nation’s highways due to supply and demand of the need to recharge. Because of that, charging stations will likely implement a cost well beyond the cost of electricity for the use of the charging station.

More fossil fuels will be needed to create the energy for electric cars.

Dealing with stray electricity. Change in service intervals, keeping up the electric grid.

Insufficient power generating capacity to supply a large population of electric cars. This will drive cost of electricity up, essentially forcing all consumers to subsidize EVs (supply and demand). Continued expansive intrusion of government interference with free market forces.

Environmental concerns with battery disposal is one, and lack of training on how to properly diagnose these systems.

Utilities being able to produce enough power to recharge vehicles. Who pays for the infrastructure needed to recharge vehicles?

Not enough properly trained technicians to maintain the EVs.

Market for engine and gear oil will shrink. After all, less lubricants are needed than for an ICE. Greases not affected.

The most positive consequence would definitely be the lowering of carbon footprints and improvement in the health of people, particularly in newly industrializing countries and developing countries. This also would lead to the R&D of new technologies, particularly in battery technology, storage devices and chemical fluids.

One negative consequence is a dramatic reduction of investments into lubricant research. Corporations fear that ICE and diesel engine oil markets will shrink, so during the last several years they don’t try to develop new base stocks or additives. They also are reducing the overall tribology research expenditures, including personnel.

Loss of road tax from liquid fuel sales, overburdened electrical grids.

Safety, battery fires. Environmental, battery disposal.

For this topic, the real challenge will definitely be how to keep moving forward when vehicles don’t need the same volume of lubricant as they currently do.

Original cost and resale as well as battery life are possible areas that might not proceed as expected. It is a new game after all.
 
Editor’s Note: Sounding Board is based on an informal poll of 15,000 TLT readers. Views expressed are those of the respondents and do not reflect the opinions of the Society of Tribologists and Lubrication Engineers. STLE does not vouch for the technical accuracy of opinions expressed in Sounding Board, nor does inclusion of a comment represent an endorsement of the technology by STLE.