I think you are missing my point Donald ie. we are talking about caring for a battery of an EV and with that comes different ideas from people on how to do that …no less valid that yours…even with your expansive knowledge about Li-battery. You say it is ‘simple’ as if there is only one way ie. yours …there isn’t…there are many ways as the other voices here suggest. I would also be interested in learning what Renault (battery division) suggests too and imagine it may well be different advice that you have given and they are ‘the experts’.

Donald,

I agree with you on battery chemistry, Zoe is “lower end”, but the mechanisms are well understood.

Since Zoe doesn’t use the full capacity of the battery, life time of the battery is greatly increased over what we know from laptops or smartphones. You can see in winter how careful the battery management system of the Zoe handles the recharging (I have longer charging times, I see a significantly reduced recuperation a.s.o.)

My point was: if I treat my battery the way you suggested, I may gain some extra life time, but I doubt that my battery will last more than 3 months longer than a fully charged one, if the climate conditions are the same (Temperature is an ageing factor as well and we all know the sound of the two ventilators in our Zoes when charging in Summer).

So maybe the “100% chargers” get a new battery three month faster than you, but they always had the full capacity available while you “crippled” your car over several years with 80% charging.

Another fact that weakens your point is that Renault said, it would charge us 2€ per 43 kW charge. How many of you have paid for 43 kW charges? Nobody, I assume, because Renault became aware that even a 43 kW charge (2C) does not affect lifetime of the battery significantly.

Next point: all other manufactures give 8 years of warranty on their batteries with comparable chemistry. They wouldn’t do that if the degradation of the battery would be that sharp.

Do you want to charge to 75% for 10 years? I don’t.

Regards
Umbi

I don’t think there are therefore any definitive answers in best way to use battery because we are the early adopters and are as such guessing best ways to use and will all have different views and theories. They are just that ‘views’ + ‘theories’ and I feel we have to come to our own personal conclusions about this.

Though that’s certainly true from the perspective of the use and life performance of EV-specific Li-ion batteries, the facts are well understood for Li-batteries in general. There is little ‘new technology’ in automotive Li batteries that is not already know. Indeed, it is only because Li-ion are now sufficiently well understood that VMs are prepared to risk the huge cost of installing them in cars.

So the question does not really revolve around Li-ion batteries as these have now been made and used in their billions for 20 years, the question is whether EV use presents any additional challenges not yet known, or any particularly beneficial aspects that mean they are less aged by having 100’s of Amps drawn from them (which I have to doubt!).

My comments have all related to the general case for Li-ion batteries and if you treat your phone and laptop batteries in the same way I have suggested, those will last longer too. Of course, as has been mentioned, these batteries, be they in cars or laptops, have to meet their warranty expectations, and so if you charge up to 100% every time then that’s what they are *intended* to do. Fine. And if you do that you can expect the ‘full life’ from them as quoted by the supplier.

My only point is that if you do exercise them fully, all the time, then they may well meet the full stated life but don’t expect anything better! If you do want to get something better from the batteries, be more gentle with them. So you have an ongoing warranty with the Renault battery lease. Yep. And the guarantee is 75% capacity. If you are happy with that after a couple of years, then that’s just fine and everyone’s happy. But you can’t complain if that’s all your battery delivers after a couple of years if you push it to its limits every time. The reason you can’t complain is because it has delivered the stated performance.

If you want better than the stated performance from your batteries, then you have to treat them better than the minimum due care.

So it’s quite simple really. Be happy with 75% health and charge 100% every day, or nurse the battery a little and kept 95% health at 80% charge.

You might note that 80% of 95%SOC is the same as 100% of 75%SOC, so are you really not getting ‘what you expect’ if you keep your charge to 80% of a fully healthy battery?

In other words, if you are happy with the warranty terms of 75% original capacity, why not just charge to 75%SOC when you still have the original capacity?

In my point of view I will also be driving my Zoe (whenever she may arrive) without caring for the battery. This is why I will have a lease.

I don’t know about the “active cooling of the battery”-part. I think there is active cooling of the CHARGER but not the battery. Since I don’t own a Zoe I can’t confirm this.

I do however belief that the Chameleon charger is more gentle on the battery and will have battery longevity in mind. But like all batteries Zoe will get less capacity over time. How much less and in what time is a big unknown at the moment. I would personally be very happy to purchase the battery instead of leasing it but since Renault don’t offer this anywhere else except in Norway (lucky b…) this is a no go. The other thing is that any cell replacements will have to be done in France at the factory as no garage that I know of here in Ireland is equipt or willing to do high voltage electric work. Renault is more likely to ship out a whole battery unit, swap it around and then repair the old unit in France. Replacing a battery unit in Zoe is, to my knowledge, very simple and safe as it was designed with battery swap stations of the now defunct “Better Place”.

I am gathering that perhaps this debate is ensuing (amongst laymen) because this technology is so new and as Donald suggests Renault may not have all the answers as not enough use and results over a period of time in the real world as yet. Which brings an aspect of the unknown + uncertainty.

I don’t think there are therefore any definitive answers in best way to use battery because we are the early adopters and are as such guessing best ways to use and will all have different views and theories. They are just that ‘views’ + ‘theories’ and I feel we have to come to our own personal conclusions about this.

I just want to drive her and not have to think too much about my battery. However I would like Renault to have a best way of looking after your battery guide though and will ask for this.

You are correct that I am not so sure of the Zoe, but evwerks have stripped the Fluence battery and found exactly the same modules as in the Leaf. I believe these are all standard LGChem 60Ah [nominal] modules in Renault/Nissan. It makes no sense I can comprehend for them to stock slightly different size modules. They would vary naturally, and have to be matched.

They would be obliged to match modules, so if they had a stock of modules measuring as 65Ah then they’d have to match those to other 65Ah packs. It’s bad to string a serial set of modules with differing capacities. I’d imagine the capacities could easily be given an acceptable tolerance between 65Ah and 55Ah (meaning battery packs of 26kWh to 22kWh).

Sorry, I don’t understand your question “What’s the point in getting a new battery according to your leasing option 3 months later but have years of limited range?”

What makes you so sure that you’re figures are correct? What’s written on the label of your Zoe battery?

As you said: the battery will age. I doubt the 5 yrs/10 yrs you mentioned.
What’s the point in getting a new battery according to your leasing option 3 months later but have years of limited range?

Regards
Umbi

Everyone I have spoken with so far who works for Renault seems to know only scant details about the ZE range, and most of what they claim to know has simply been wrong.

The battery is a 24kWh battery, and you have access to around 21.4kWh of it. Renault calls that a ’22kWh’ battery.

Charging to 100% and rapid charging does not harm the Zoe’s battery.

This depends wholly on what you mean by ‘harm’. If you mean it causes ageing of the battery, then everything causes ‘harm’. Using the battery causes harm. Not using the battery causes less harm but the battery still ages. It ages and it will die whatever you do, it is only a question of what you do that accelerates or slows the ageing process. It is not ‘if’, it is only ‘when’.

The best Li batteries for life time are Lithium titanate, but they are expensive. They would last the rest of an owner’s lifetime. Lithium manganese oxide is almost the worst chemistry for longevity, but is cheap. This is what Renault/Nissan use. They will last 10 years if treated nicely, 5 years if treated badly. Even less if the car is kept in +35C temperatures for long.

The more you pull high power from the battery, the quicker the electrolyte will self-oxidise and cause the electrodes to get coated in inert reaction products, which increases the internal resistance, thus self-heating of the battery and further accelerates ageing. When the cells get to high volts there is a phase change in the electrodes, which accelerates ageing. Whatever way you wish to convince yourself otherwise, using (charging/discharging) the battery gently and keeping it as close to 50% state of charge as you can for as much time as you can will reduce the ageing effects.

As a matter of fact the Zoe battery has about 26 kWh (check for a label on the underside of your car, mine says 25800 sth) und 22 kWh is free for usage.

That is 100% Zoe is not 100% battery. And 0% is not 0% battery (but you need a flat bed anyway).

This is common in all elctric cars to avoid early aging. That way the battery should last several years with more than 80% of the capacity. I don’t think that Donalds proposal will make the battery last significantly longer.

Regards
Umbi