[RahulNagaraj]

Electric cars are slowly gaining popularity and acceptance across different markets. Sales of electric vehicles have also been on the rise, with many carmakers slowly introducing multiple products in the segment.

With the number of electric vehicles on offer, it isn’t surprising to see that these vehicles are also finding their way into the used car market. However, evaluating a used electric car is very different from that of its gas-powered counterpart.



This is because the main component which needs to be evaluated in an electric vehicle is its batteries. However, there is currently no way for customers to do that.

Lithium-ion batteries in cars, similar to those in smartphones or other electronic appliances, tend to lose their capability of holding their charge, after being used over a period of time.



While high-end electric vehicles such as the Tesla models do manage to hold their health very well. They make use of advanced technologies, which is also one of the reasons for their premium price tags. However, this is not true for the mass market EVs, which cut costs and may not be as technically advanced as a Tesla.



According to a report, the Tesla Model S and X are said to be capable of retaining over 80% of their capacity even after covering 200,000 miles. On the other hand, a cheaper EV such as a Nissan Leaf is said to be notorious for its battery degradation. This is because it misses out on a battery temperature management system, resulting in a rapid drop in its battery health.



Another problem is that electric vehicles are yet to become as common as gas-powered vehicles, especially in the used car market. This means that there is very little information for potential buyers to look back on.

According to the report, one possible method to get an approximation of an electric car's battery health is by checking the estimated range when it is charged to 100%.

Source: Vice.com

Link to Team-BHP News

[Everlearner]

There had to be some scientific method to test and certify the battery health either by service centers or by third-party agencies. When a used iPhone is put up on sale, I see mention of battery health in number of cycles or %. The govt/ARAI should work on standardising battery testing to bring uniformity and evaluate batteries objectively.

[PrideRed]

This is the exact issue I mentioned in thread: https://www.team-bhp.com/forum/elect...tric-cars.html (Concerns over the resale value of electric cars)

I strongly feel EV's will be treated similar to Mobile phones in used car market. While depreciation may not be as much as phone, but definitely much higher than gasoline.

[niceguisuku]

While battery is the important component, there are other things also to be checked

• EVs tend to depreciate faster than ICE cars according to studies. So knowing right price based on depreciation is also difficult. The advantage is that you get maximum value when buying EVs.
• As technology around EVs improves faster, you might find yourself with outdated technology when buying used EV.

[landcruiser123]

For many years, the hybrid battery cells of the Toyota Prius are tested by professional mechanics using a computer and specialized software. I'm sure the devices & programs will be commonplace at dealers and independent mechanics who can figure out the remaining life of the battery for EVs.

[GTO]

Agreed that it will be very easy to gauge battery health - heck, all cars will eventually give you an option onboard to do so. But I will also state that Tesla is surely an outlier in the way that its batteries are so healthy even after 7 - 8 years of use. I don't think a mass market car (e.g. Nexon) will have its batteries in such good shape after so many years. One reason is the cheaper battery of lower end cars, but the other is also the understanding of the same. I think Tesla is 5 years ahead of everyone else there.

But hey, the battery of EVs will also be easier to swap than say, an engine .

[starke]

What I feel from my experience in the EV field is that the resale would become much easier for a buyer as well as the seller when compared to an ICE.

Because like a smartphone, especially if you take iPhone, the resale value is directly linked with battery health now. So considering no risk of multiple moving part inspection for an ICE engine, a simple battery health check will define the price of the EV in that particular time.

For example, after 5 years, a Nexon EV in the used market will be priced based on the range it can produce. One with 200 Km will be around 6 to 8 lakhs, 150 km will be around 5 to 6 lakhs... So a proportionate price factor against the range or Battery SoH will be laid.

Usually, the traction motors (EV motors) are less prone to damage or wear n tear when compared to an ICE/Gearbox and it will be easy to measure the wear n tear based on the thickness of its winding and all. Apart from the normal wear n tear parts like suspension, rusting of body, brakes etc which is common among the two, EVs will make the used market much easier than buying an ICE car.

[srini1785]

EV vehicles (essentially motor and allied electronics) and batteries are two different techs. A company that aims to be a leader in EV's should accept that it can't master battery tech. We would, in near future, look at only the vehicles from car companies while the batteries would come from another company. This would lead to a level of customization that is not possible with a ICE. Sample this , a Hatchback can come with batteries ranging from 20kwH to say 100kwH depending on your need. So it you want a slow moving car with an amp that scares even the hardcore hard rock fan, sure you have the battery for it. All it needs is standardization in terms of mounting and charging. Further, it would not be surprising that traditional car companies like Ford, Toyota, Ferrari et all slowly bowing out to companies like Toshiba, Mitsubishi, ABB etc who have the motor tech.

In other words, welcome to the world of use-n-throw electronics.

[flanker]

Originally Posted by GTO

But I will also state that Tesla is surely an outlier in the way that its batteries are so healthy even after 7 - 8 years of use. I don't think a mass market car (e.g. Nexon) will have its batteries in such good shape after so many years..

Specifically in case of Nexon, the battery should have a longer lifespan since it has a lithium ion phosphate battery. LiFePO4 are less power dense but have a much larger cycle.

As for now, there is a version of Model 3 with LiFePO4 but most other/older Tesla cars use a battery chemistry that have lesser cycle life.

Off topic:
The problem with some manufacturers will not be the battery itself, but software implementation over it. MG ZS EV's old BMS (still current in India) has a meager top buffer that can lead to battery degradation. They fixed this in some countries with a BMS update(s). One such BMS update had another bug that broke the battery balancing.

And then there are batteries with inadequate cooling or passive cooling (older gen Nissan Leaf).

All these implementation issues can certainly lead to shortened battery lifespan and can be a major concern while buying an used EV.

In India, the one biggest factor for battery life will be ambient temperature. All lithium ion batteries degrade even when not in use when subjected to high temperatures. This will be more crucial than even the cycles and depth of cycles.

Before buying a used EV, I would probe the OBD and get battery balance figure, max charge voltage per cell. And if possible do an extended drive to calculate the actual capacity of the battery.

[fordday]

Originally Posted by starke

Usually, the traction motors (EV motors) are less prone to damage or wear n tear when compared to an ICE/Gearbox and it will be easy to measure the wear n tear based on the thickness of its winding and all.

Do the motor windings lose its thickness over usage or time period? I never knew this.

[srini1785]

Originally Posted by fordday

Do the motor windings lose its thickness over usage or time period? I never knew this.

Motor conductor wires are enamel insulated. They are abrasion resistant but not entirely protected against mechanical wear.

https://www.acorn-ind.co.uk/insight/...motor-failure/

See Point 2.

[Slowjet]

The price of battery which was close to $1000/kwh about a decade back has come down to approx $150-175/kwh and this is going to reduce further. The battery for cars is in the form of modules. So there no no need to change the entire battery pack but only a particular module if it not functioning properly. In future, we may also see battery swapping station where one can subscribe and swap the batteries as fast as something similar to filling petrol. Coming to Tesla battery, it is Panasonic that manufactures it. Range / life depends on the chemistry and cathode material used. ABB has developed flash charging TOSA that is undergoing testing which can charge a bus using overhead charger of 650KW in 20 sec.

With progress being made in technology, I think if a used car has a battery problem, the costs for a new battery / subscription model for swapping / replacement of a module will not be high.

There are many companies in battery manufacturing like Sony, Panasonic, Samsung, LG to name a few. and automobile companies have a tie up with them where they jointly develop the technology.

[lina]

Originally Posted by GTO

Agreed that it will be very easy to gauge battery health - heck, all cars will eventually give you an option onboard to do so. But I will also state that Tesla is surely an outlier in the way that its batteries are so healthy even after 7 - 8 years of use. I don't think a mass market car (e.g. Nexon) will have its batteries in such good shape after so many years. One reason is the cheaper battery of lower end cars, but the other is also the understanding of the same. I think Tesla is 5 years ahead of everyone else there.

But hey, the battery of EVs will also be easier to swap than say, an engine .

Also, lower capacity batteries will go through more cycles thus degrading faster. Apart from range, this is another reason to have a bigger battery. You will get much longer life thanks to fewer cycles and respectable capacity even after degradation.