[aim120]

Originally Posted by Garth

One gentleman wants to install a fast charger in the basement parking routing the cables from his home or his BESCOM meter (which is in the basement).

Hearing all the stories of EVs catching fire while charging, everyone is opposing. Particularly as there are other petrol/ diesel vehicles parked close to this guy's parking. The fear is that if anything goes wrong, all fossil fuel vehicles could catch fire and maybe endanger the building itself.

P.S. - Our apartment has multiple slow chargers installed at the entrance. But this one smart alec insists he wants to have a fast charger.

Would like to hear views from the knowledgeable folks here.

A fast charger? Do you mean a a home charger like a 3.3kw or 7kw unit. Its not fast, its fast compared to US 110v standards.

A 3kw charger on a nexon is like charging your smart phone with a usb 2.0 computer port, a 7kw is like charging with a usb 3.0 port. Since the battery in nexon is still being charged at 0.1C with a 3kw charger and a nexon max with 7kw charger is still being chargeed less then 0.2c. So there is very little heat made from the battery charging, just like your smart phone if charged with a usb 2.0 port with 500ma output.

But it will put more load on the apartment transformer, if everyone starts fixing 3kw or 7kw chargers. Once the load is enough to saturate the existing transformer, it will start giving low voltage and then start getting hotter and hotter, until it fails, which will be spectacular in terms of fireworks.

Even if you use a portable charger aka granny charger, for what ever reason if there is a short or arc, it will cause fire.

If the vehicle has a lipo or NMC/NCA chemistry battery like 2020 MG ZS with 40kwh battery or hyundai Kona, Ioniq 5 or Kia EV6 ,these batteries when they fail or have a short will cause thermal runaway. The batteries themself can sustain or start new fires.

But if its a Tata nexon/Max, Tiago/Tigor, BYD, MG ZS 50kwh face lift version, these have LFP battery which by themselves will not contribute to a fire. But just like any battery including lead acid battery in your IC vehicle, if you short the postive and negative terminals which creates a Arc, it may cause fire to other flammable material like carpet, plastics etc.

So which vehicle does he have.

[Garth]

Originally Posted by aim120

A fast charger? Do you mean a a home charger like a 3.3kw or 7kw unit. Its not fast, its fast compared to US 110v standards.

Thanks, I think I missed that. He really meant a home charger and not a fast charger. Probably he might have meant his 7 kw home charger than the society 3 kw charger.


The point on transformers is also fairly valid.

He has booked a Nexon EV

[GTO]

Originally Posted by Turbanator

I won't recommend the setup, definitely not for overnight (unattended). There should be a place above the ground to place temporary charger, under cover (what if it starts rain in the night?) and with a separate MCB/ ELCB.

But of course! This is used for EVs just once a month or once in two months, and primarily during the day with someone watching over. Reason = I don't own an EV yet .

The plugs are currently used for the Bosch C7, with the actual charger unit placed inside the car (under the bonnet).

When I buy an EV, there will be a waterproof box for the charger.

Also, we should ensure that earthing of the house is good and checked after a couple of years, especially for all EV households. It will be a good idea if we get separate earth only for EV charging. Some of the manufacturers like BMW (ABB) insist on this.

All fresh wiring for the chargers in my compound, right up to the source, with the relevant MCBs / ELCBs.

[navinmra]

Originally Posted by das_ren_auto

Sir is there an issue if the car is plugged in daily overnight to gain around 30% charge?That is from 50 to 80 percent daily.

This is my question as well. Albeit a little different. Every time my Nexon EV Max SoC drops to 30% or thereabouts i slow charge it at home to 80%. I saw a video quoting a research from battery institute that this sort of cycle generates the least heat and keeps the battery health intact for longer than the usual 3000 cycles quoted for LFP chemistry. Is this true? And if so, how does that tie into TaMo’s advice of charging to 100% once a week ( I will interpret as once a few cycles)?

[sameer sultan]

Thank you GTO for this wonderful post. I just discovered it while reading the Nexon.EV review.

Recently we got a MG Comet in my extended family so I got to use it for 2 weeks just to get a feel of the EV in real world conditions with my daily commute routine as in future I am thinking of getting an EV of my own.

I used the 15A socket to charge the Comet, there was no provision in my parking lot for having the plug points so what I did was is to get a wire extension from my home to the parking lot and charged the EV it was so convenient and easy with no extra expense of installing a 15A socket in the parking lot.



I have 2 queries.

When you charge an EV overnight for a 60% charge in about 8 hours through the 15A plug point how many units of electricity will be consumed?

I have read in this post where some people are charging their EV’s in their office parking lots, does the office foot the bill or how does it work? I am just curious as one cannot use a plug point in a public place to charge one’s personal EV just like that!

[carthick1000]

Originally Posted by sameer sultan

When you charge an EV overnight for a 60% charge in about 8 hours through the 15A plug point how many units of electricity will be consumed?

Comet has a battery capacity of 17.3kWh. Usually there is a nett (usable) and Gross (Latent/unusable) value for every battery pack. MG did not provide this split. For ease of calculating, lets assume the specific value above. Say if you charge from 10% to 60%, that is half (50%) the battery capacity. 17.3/2 = 8.65kWh. Let us assume losses of 5% from charging cable from ur home to car.

8.65kWh + (5% of 8.65kWh) => 8.65kWh + 0.43kWh = 9.08kWh or 9.08units of electricity.

[sj@8535]

Yes I completely agree regarding the use of regular 16/20 ampere plug points.

I have a Nexon ev, someone authorised by tata installed the 16 ampere plug which was from a branded company. But the problem with this is that it overheats a lot . I have another 16amp plug which I installed parallel to the Tata plug point -i bought some random brand with clay base that seemed cheaper and to be of good quality. This plug point works fine !

[rsidd]

Originally Posted by GTO

- With any EV, the initial 0 – 80% charging is faster than the final 81 – 100%. For city commuting, I doubt anyone needs a level over 80%. And just FYI, a Tigor EV goes from 0 – 80% in 8.5 hours. Most cars in India are parked overnight for durations longer than 8.5 hours. Fact = many informed EV owners intentionally don’t go over 80% charge levels to preserve battery health.

Belated reply since I just saw this thread. I do see this advice of not going above 80% online, but not sure how correct it is; it could be derived from mobile phone/laptop advice.

The Tata manual recommends slow AC charging to 100%, and specifically, after four fast DC charges, the manual strongly recommends slow AC charging to 100%.

I also see this advice elsewhere: "The Tata Motors team have observed owners charging the battery of the car up to 60-70% each week as they feel that is enough range for their day-to-day needs. But this becomes a big issue as all the cells in the battery pack won't have optimum balanced voltage. When this happens, even if one cell goes below the threshold the car will stall. So it is recommended to Nexon EV owners to leave your car to charge overnight once a week. And ensure it charges up to 100% SOC."

Also, while the manual tells you never to let the charge go to zero (and not to attempt charging if it does go to zero), it seems like letting it go below 10% now and then helps better calibrate the system.

So can I request you (GTO) to double-check the recommendations and, if required, edit the post.

[electric_eel]

Originally Posted by rsidd

Belated reply since I just saw this thread. I do see this advice of not going above 80% online, but not sure how correct it is; it could be derived from mobile phone/laptop advice.

The Tata manual recommends slow AC charging to 100%, and specifically, after four fast DC charges, the manual strongly recommends slow AC charging to 100%.


[snip]


So can I request you (GTO) to double-check the recommendations and, if required, edit the post.

Yes I agree with you @rsidd. The general advice should be to follow the manufacturers recommendation given in the manual. In general LFP based battery systems that have an almost flat discharge curve needs charging till 100%. Not because it improves the life (actually it probably reduces) but because the BMS has a hard time figuring out the SoC otherwise. For NMCs it is okey to charge till 80% but even here it is better to follow the manual. For all you know the BMS might already be accounting for this variation.

In any case one does not need to worry about the battery life too much as modern battery pack with its BMS can out last the car often (Be it NMC or LFP). So it is the other factors (like better SoC prediction) etc that matters most for a user.

[rsidd]

Originally Posted by electric_eel

In general LFP based battery systems that have an almost flat discharge curve needs charging till 100%. Not because it improves the life (actually it probably reduces) but because the BMS has a hard time figuring out the SoC otherwise.

Yes, I think this is exactly it. Elsewhere, @ferrarirules writes (Tata Tiago Electric Review)

1. Always charge to 100% as much as possible. Not necessary on a fast charger.
2. There should be one charge below 20% to 100% in every 4 charges
3. There should be one charge below 10% to 100% once in a month

(the above is for Tata/MG cars).

@GTO, please do edit the first post in this thread, which will be seen by many since it is "parked". At a minimum, users should do what the manufacturer recommends.

[supermax]

Originally Posted by rsidd

@GTO, please do edit the first post in this thread, which will be seen by many since it is "parked". At a minimum, users should do what the manufacturer recommends.

I don't think @GTO is telling anyone to go against manufacturer recommendations. The point he's making is that nobody would really take the battery down to 0% anyway, and if you are at 30 or 40%, you'll definitely have brought it up to 100% by the next day, after a full night's charge. In the event that you had to leave early or got home late, you'd still be likely charged up to 80% or more, which is not at all bad is what he's saying, IMO, and even though I'm rather skeptical about EVs, the logic is sound here.

[writetoavi]

Absolutely agree with GTO. For a normal usage it works like a charm.
Yes get the manufacturers one installed but they have also given a normal plug point the basic ev charger, so use them very effectively.

[anksoft]

I am buying Ioniq5 and plan to use 15A charging ( I am in a rented home with less than 100km per week). Though this needs to be installed outside. So wondering what is easiest ready made solution to install a 15 A socket. Would it be possible to install a ziptron box without a tata ev? Are there other similar solutions?

[randeepsr]

When your power supply is erratic. (City outskirts in an independent home). So electric supply is flaky and goes through big surges and dips. Over my last 9 years of my electric car E2O ownership; I have blown out my car charger around 4 times. Finally I put a voltage stabilizer to take care of such surges (5KVA). Even when I switched to new electric car; I still kept the stabilizer. Picture for reference.

[das_ren_auto]

Originally Posted by randeepsr

When your power supply is erratic. (City outskirts in an independent home). So electric supply is flaky and goes through big surges and dips. Over my last 9 years of my electric car E2O ownership; I have blown out my car charger around 4 times. Finally I put a voltage stabilizer to take care of such surges (5KVA). Even when I switched to new electric car; I still kept the stabilizer. Picture for reference.

Can you share the details of Voltage Stabilizer's brand, model number/name platform of purchase etc.