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Thanks for the detailed response. Correct me if I am wrong, they accounted for only for cathode recycling. Not electrolyte and other parts. Also, EV batteries have much larger intrinsic value as second life as after 70% SOH they can very well used for other purposes.

As for the figures, I will only talk about ZS EV as I know the efficiency figures. It is a 4.3 m car comparable to creta etc. For city use these cars at best will return 12 to 15 km/L i.e 6 to 7 L per 100 km ( am being generous). On the other side the ZS EV does about 8 to 10 km/kwh which is 100 - 125 wh/km.

Is my math wrong?

How I wish there was more analysis done on such an important policy topic and put in a form that a lay person like me could understand.

I do not understand the nitty gritty of the recycling processes chosen, the cited study has taken data from some Chinese companies currently involved in commercial recycling (since equivalent data does not exist for India). That data seems to indicate recovery of not just the cathode material, but i could be mistaken given my limited undertanding.

The basic assumption of the study is Based on this, I doubt there would be any repurposed usage possibility (16year+2L km mileage battery).
Given this, the EV has benefits vs ICE
- if the EV is used for 1L+ kms
- uses solar/grid power from non fossil fuels
- recycle the batteries

I think the bottom line at present is
If some one in South/North of India using an EV with grid power, the emissions will be lesser compared to an ICE.
Whereas a EV user in Western/Eastern India is using the EV with grid power, they more likely are increasing the emissions (compare to usage of an ICE) !

Yes, I think you are correct.
I suppose the ARAI figures would have been used for the study.
But, note that this is based on all india average (not based on the region) based on a projected grid distribution in 2030, we are 8 years from it, and the current -ve differential for the western and eastern regions would continue.

Which again begs the question- why cannot policy makers start commissioning studies based on real world data rather than extrapolation, and put up the results in a manner a lay person can understand ?

I think this assumption is not correct. The battery will reach about 70% and then it will not be suitable for the current demand of the specific EV. It will still have good few years for other non-transport use.

If we have to project the long-term viability of an EV bought today, then we will have to look at the projection for at least 2030.


The issue is that most of these studies are commissioned by likes of Toyota who have a very large vested interest into keeping the status quo. No one else has any interest.

As a lay person, two years ago, I had to decide whether I want to buy another ICE car or an EV for next 10 to 15 years. If we keep going the ICE route then there is no solution possible for neither carbon pollution or the particulate pollution. And that to me was an easy choice to make.

The article there is not too accurate. And let me tell you why. A battery that falls from 100% SoH to 70% SoH will not give you exactly 70% of the original kWh rating. On the contrary, its ability to operate as an EV car battery gets compromised. Once a Li ion battery has its SoH dip below 80% the behavior starts getting deeply erratic. It is in fact labeled as second life and moved to more docile work such as being operated as a UPS battery.

The way a battery operates is dependent on factors such as the battery chemistry. Tesla has its very own NCA (Lithium Nickel Cadmium Aluminium) which has proved itself very well over a period of time. Model 3s built in 2013 and having run over 150k miles still have over 90% SoH which is very encouraging. Owners who maintain a Depth of Discharge (DoD - explained in my earlier post) of 80-90% regularly enjoy great SoH over long periods of time. Regular fast charging, operating the car in extreme temperatures, etc plays a pivotal role in maintaining the SoH of a battery

I recommend all to go through the brilliant site https://batteryuniversity.com/ to understand more on this subject

I have used lithium cells made custom battery pack in RC cars/drones etc both in prismatic and cylindrical form since more then a decade, to some extent what you say is true, particularly the raw acceleration may be become lower. But this cannot be generalised for all battery chemistry or sizes.

As long as the battery pack can still give out 100% of the power that motor demands, there wont be a drop in acceleration.
Any battery can give out 5x or more power proportional to its current capacity for several seconds or even minutes.

But if you say that the EV cannot be used after 70% SOH then you are wrong, 70% SOH of a 100kwh battery is 70kwh. That 70kwh battery can still behave like a car bought with 70kwh battery when new.

This is probably true right now, but it is very important to consider that EVs are powered by any type of electricity.

What I mean by this is that buying an EV with a 10-15 yr service life today means it can be cleaned up by any improvement in the grid. This means that if the owner (in a single home context) installs solar, the car gets cleaner. If large offshore wind projects come online, the car gets cleaner. If coal is replaced by natural gas (not ideal, but better), the car gets cleaner.

On the point of solar, the economics of shifting to solar improve if one owns an EV. Either in a single home context or someone running a fleet. The amount of energy used by one's own transport is far more than running one's home. Cutting the cost of electricity for the house AND car makes break even much quicker.

The point here is that EVs can "bake-in" future improvements which cannot happen with fossil cars.

There's also the point of urban air quality which others have made so I do not need to add to it.

Here's an interesting article. Notice that everything radiates from Las Vegas!

https://elements.visualcapitalist.co...c-cars-vs-gas/

Hope it's entertaining :)

Exactly my point, shouldn't the govt. also have supported/comissioned some studies for such an important policy?


Agree with you on all the counts.
Unfortunately, these seem to be based on so many IFs. Current policy seems to be geared towards "appearing" to be clean.

We run the risk of going the carbon credits where the touted offsets are in reality, at best keeping status quo. Refer to the following article for a quick primer https://qz.com/2009746/not-all-carbo...any-still-are/

Question for the owners/experts here, in EVs with regen level selection how does it affect regen during braking. As I understand,

1. Regen level primarily influences how aggressively regen happens when foot is taken of the accelerator. So in off/level 0 setting, no regen happens when foot is off, good for highway driving. Highest level of regen is good for one pedal driving in bumper to bumper traffic and some where in between to suit driving conditions. Cars with fixed regen level are probably set some where in between.
2. Braking first does regen, but when requested braking exceeds limit of regen braking force, mechanical brakes kick in. Question is whether this is affected by regen level setting.
3. Similarly, during cruise control when car needs to slow down braking force is supplied by regen and/or mechanical brakes as required. Again would this be affected by regen level setting.

Seems, to me regen level setting should only influence what happens when A pedal is eased, but wanted to confirm my understanding.

My take is that braking as a function is so critical that its functionality will continue to be as designed, i.e triggered off by mechanical action or ADAS
Whatever power can be harvested from this function will be done as a consequence of the braking action. Whether done manually or triggered off by ADAS
ALL power harnessed through regeneration is used to recharge the batteries. A small part may be used to release brake function at the point of starting the car however
Regen levels should not be influencing braking efficiency
Your final statement is true on regeneration levels influencing only how the car behaves when acceleration pedal is released

Open to be corrected on this understanding

While our EV discussions are just starting off, the stage is set for over 150 EV launches in the US in the next few years. And this video has a preview of some droolworthy EV launches in the US in 2023.

https://youtu.be/WFrxhfjV7oI

That is correct.

Correct. The Nexon EV max also has an iVBAC system to provide maximum regen even when using the brake pedal. I suppose that the other EVs in this price (20L) would also possess this tech, but I can only confirm for the Nexon max due to it being explicitly mentioned.

Cruise control uses regen to modulate speed such as, say, when you’re going down a flyover. This is irrespective of the regen mode you’re in.

CC will use regen to modulate. The CC on our 21’ Nexon would rather let speed blip past the limit (2-3km/h at most) if the slope is too steep than use pad brakes. That is why I conclude that pad brakes are not used in CC mode.

A little off-track from BYD, but relevant for the long term ownership of EVs, not just this one. The future of auto does not only depend on the brand or model, but on the environment in which they need to grow.
The Govt. determines the future of all businesses, and EVs are no different. The Indian govt. seems not to put their weight behind EVs. It's got to do with self-reliance on the entire ore-to-car supply chain. We will not win here, and it's quite clear.
You see clear indications of this. The EV subsidies are going away, there are no special incentives being rolled out, or are being discounted. The new energy policy from the Gadkari ministry seems to turn towards Green Hydrogen. Primarily, this is to take away the reliance on battery tech, where China and the US more or less control the supply and the tech. There are too many defensive patents being filled, where Indian manufacturers will end up payment either paying royalty or inputs costs from supplier will end up being high.
Somehow, the govt. feels that India can manufacture hydrogen with renewable energy and nuclear. Even though the final prime mover will be a motor, the energy transmission with be from the fuel cell and not the battery. This is supposedly good for larger modes of transport like trucks too. But, the jury is still out. So time will tell.
Build the infra for charging grid and the backbone grid to support this is very tough. Given the India has just reached a tipping point on electrification of most of the villages, it's not designed for pulsating, high demand power trasmission and peak load handling.
While is not difficult for EV manufacturers especially Indian brand that have repurposed IC frames to accommodate batteries, to switch to green hydrogen, EV only platforms like BYD might find it hard.
Anyways, it's still initial days for both the technologies.

I don't know how you can be so wrong while also being irrelevant.

I am sorry but I don't think you have the full picture to discuss on this topic. I would suggest going over news articles than sounding like an opposition party.

I am sure most of us are tired of answering to these kind of posts.

No harm in discussing emerging tech, one more post, never hurt anyone. I don't have any political affiliation, it does not matter, irrelevant to this dicsussion.
I guess we all have a fairly good view around these topics, maybe some have the view from the perch.
There is a larger 'move away from oil' at play here, not restricted to EVs only.
Here is a post that helps (read at your own peril of opportunity cost of time).

https://www.linkedin.com/posts/paras...920118273-8bBs

There is more material in and around this, tons of it.

What is true around the world, is (need not) be true here.

My only view, is that the long term strategy of what will post oil look like is not sealed. There is a tiered approach to this, 2W are different from cars etc. anyway not relevant for BYD.

But in many aways, BYD raises the same question, sustained growth possible?