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Old 2nd March 2020, 10:57   #16
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Re: Some technical questions on Electric Vehicles

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Originally Posted by ds.raikkonen View Post
Thanks, where is it packaged?
From Kona official review.

Some technical questions on Electric Vehicles-2019hyundaikona07.jpg
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Old 2nd March 2020, 14:39   #17
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Re: Some technical questions on Electric Vehicles

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Originally Posted by vibbs View Post
I have another question to those who intend to buy EVs but stay in apartments. I assume you will have to draw in cables from your main supply to set up a charging point near your parking place. How do we ensure that power theft does not happen in such cases. I mean anyone can drive up and charge their car when you are not around. Or is it under lock and key?
Keep an ON/OFF switch in the house - simple. They just need to switch it on when needed. And switch it off when the car app shows battery at 100%.
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Old 2nd March 2020, 18:23   #18
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Re: Some technical questions on Electric Vehicles

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Originally Posted by vibbs View Post
I have another question to those who intend to buy EVs but stay in apartments. I assume you will have to draw in cables from your main supply to set up a charging point near your parking place. How do we ensure that power theft does not happen in such cases. I mean anyone can drive up and charge their car when you are not around. Or is it under lock and key?
Key switch like this is an option for you..

Some technical questions on Electric Vehicles-screenshot_20200302182032002_com.miui.gallery.jpg

This is what I have done in my apartment basement parking.
Can be switched on only with key.
Connection taken from the meter room at ground floor - taking from home will be a waste of money in terms of wiring length and also overloading the incoming wiring to the apartment.

Last edited by salbin : 2nd March 2020 at 18:26. Reason: Correction
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Old 2nd March 2020, 20:14   #19
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Re: Some technical questions on Electric Vehicles

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Originally Posted by ds.raikkonen View Post
Thanks, where is it packaged? I took this photo from a Kona info kiosk in a Hyundai outlet sometime back. Didn't mention the lead acid battery.
Looks at the red circle in the layout for the Low voltage battery.

The image was taken from the Hyundai website and has basic explanation on the layout and functions of different components in a typical EV setup.

https://tech.hyundaimotorgroup.com/a...l-about-evs-1/
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Old 2nd March 2020, 23:13   #20
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Re: Some technical questions on Electric Vehicles

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Originally Posted by vibbs View Post
How do we ensure that power theft does not happen in such cases. I mean anyone can drive up and charge their car when you are not around. Or is it under lock and key?
Wall chargers are RFID activated as far as I know,so charging cable cannot be taken out of the charger unless it senses the card. Also, the car's sockets are linked with car's locking system,i.e one cannot unplug the charging cable if car is locked.

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Originally Posted by GutsyGibbon View Post
Unfortunately, the app can't do that.
Elon actually shared a video on Twitter of a robotic arm plugging in the charger,so I guess that will be soon possible.
Link : https://twitter.com/Tesla/status/629...912326146?s=19

Last edited by ADI7YAK : 2nd March 2020 at 23:35. Reason: Added link.
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Old 3rd March 2020, 00:01   #21
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Re: Some technical questions on Electric Vehicles

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Originally Posted by ADI7YAK View Post
Elon actually shared a video on Twitter of a robotic arm plugging in the charger,so I guess that will be soon possible.
Elon and his moon shot ideas! On a scale of priorities, who knows what is at the top. His house on Mars, or this. It takes all of 10 seconds to connect the cable after parking the car at home. It is usual for people to get the EV charging point installed (in their garage/regular parking spot) exactly next to where the power port of the car is. This robot seems like extreme over engineering.

I also want to point out that if one is charging their car in the driveway, outside the house, a thief cant disconnect that cable and start charging his/her EV. (steal power at night). The charging cable stays locked, and stays connected, until the EV is unlocked. The charging may stop based on the setting in the app, but cable cannot be removed. I mostly charge inside the garage, but I have left the car in the driveway while it charges. I do not have to worry about someone stealing power at night.

Last edited by GutsyGibbon : 3rd March 2020 at 00:06.
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Old 8th March 2020, 14:00   #22
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Re: Some technical questions on Electric Vehicles

There is no trickle charging for EVs, especially those running on Li Ion batteries. The charging current, voltage etc is determined by the control algorithms sitting inside the battery management system and onboard charger/charging station. These two and maybe a master vehicle ECU, if there is one, talk to each other on CAN bus and ensure that the battery is charged optimally. Plus there are contactors (basically high voltage-high current relays) inside the vehicle, which can disconnect the charger from battery if required (even if the charger cable remains plugged into the vehicle). Therefore, even if you leave the charger cable connected for a long time, the charging will automatically stop when the vehicle detects that the battery is fully charged.
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Old 8th March 2020, 14:43   #23
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Re: Some technical questions on Electric Vehicles

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Originally Posted by GutsyGibbon View Post
Elon and his moon shot ideas! On a scale of priorities, who knows what is at the top. His house on Mars, or this. It takes all of 10 seconds to connect the cable after parking the car at home. It is usual for people to get the EV charging point installed (in their garage/regular parking spot) exactly next to where the power port of the car is. This robot seems like extreme over engineering.

I also want to point out that if one is charging their car in the driveway, outside the house, a thief cant disconnect that cable and start charging his/her EV. (steal power at night). The charging cable stays locked, and stays connected, until the EV is unlocked. The charging may stop based on the setting in the app, but cable cannot be removed. I mostly charge inside the garage, but I have left the car in the driveway while it charges. I do not have to worry about someone stealing power at night.

Better yet i suppose in future we will have wireless (super)charging capability between cars and the garage floor. No need for Plug or fancy robots!
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Old 8th March 2020, 16:37   #24
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Re: Some technical questions on Electric Vehicles

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Originally Posted by vibbs View Post

I have another question to those who intend to buy EVs but stay in apartments. I assume you will have to draw in cables from your main supply to set up a charging point near your parking place. How do we ensure that power theft does not happen in such cases. I mean anyone can drive up and charge their car when you are not around. Or is it under lock and key?
The AC charger that you get with the car is activated using an RFID card. You get two of them. Merely plugging it in won’t start charging. The card needs to be tapped on the charger for it to start. So you’re pretty safe in that regard.

Some technical questions on Electric Vehicles-25246f17a2fa4cb4b87695d962ceea27.jpeg

More over the charging cable is “locked” into the car till you unlock it or deactivate charging using the RFID card so it’s not like someone can walk up to a charging car and take the cable and plug it into theirs. There is a setting on my Kona where at public charging points the cable will unlock once a desired level of charge is reached so that others can pull out the charger and use it for their own car. But it’s all entirely in your control.

Last edited by reihem : 8th March 2020 at 17:00.
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Old 9th March 2020, 09:33   #25
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Re: Some technical questions on Electric Vehicles

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Originally Posted by ADI7YAK View Post
Elon actually shared a video on Twitter of a robotic arm plugging in the charger,so I guess that will be soon possible
I won't be surprised if he does pull it off. In the EV space, he surely has proven multiple times on what can be achieved with a well engineered EV.

On charging, a more practical approach would be induction based, similar to placing your phone on a charging mat. Some car manufacturers are trying to implement this on their EV's. Could be a lot slower to charge.
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Old 9th March 2020, 09:35   #26
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Re: Some technical questions on Electric Vehicles

I am curious to know more about charging these EVs. Here are few of my questions and few of them are hypothetical too!

1. I believe regular fast charging is not recommended, so typically people will use a regular charger at home at charge overnight once in few days/week based on the car usage. So most likely a car used for regular office commute would unlikely see a fast charger ever?

2. Most of the apartments have parking in basement level-1,2 or more where there is no network connectivity. How will we monitor the status of charging in this case?

3. Will there be provision to share charge from 1 car to another car. Typically fast charge. On a long drive will there be a provision where 1 car can rescue the another car with depleted battery or will you suggest towing as the easy alternative here.

4. Will charging technologies and plugs for fast charging have standardization/plug-n-play across different manufacturers. This will be crucial to build an interoperable network for highway driving.

5. Will the cars come with a provision to add on battery booster pack for long drives. May be these can be rented/subscribed from the car manufacturer and fit in the boot
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Old 9th March 2020, 12:08   #27
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Re: Some technical questions on Electric Vehicles

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Originally Posted by Doo_Dev View Post
his battery is usually a Lead acid battery and is charged by the High voltage battery whenever the battery charges level drops below a threshold.
Yes - this is one big reason for lead acid battery in the car. But technically they could still have a 12V LiOn battery pack, instead of the lead acid one. A few reason to retain a lead acid battery, per a Tesla forum blog I read: (can't seem to find the original post):
  1. Apparently, the basic computer functions, including the Battery Management System ("BMS") run off the lead acid battery. When the car is "off", the main battery provides a "trickle-charge" to the Lead Acid battery, which in turn powers the critical computers / software running in background. Apparently, this is more effecient that connecting the computers directly into the main battery pack (not sure why this is so, something to do with reducing charge/discharge cycles on the main pack. Also, not sure why the second pack can't also be LiOn & serve the same purpose).
  2. Secondly in a scenario where both batteries go flat, the BMS would shut down and the car won't accept a charge even if you plug it in. In this case, one can at least jump charge the LA battery using a handy ICE car, get the BMS booted and plug in the Tesla. Though this could also be solved by having a "dumb" secondary LiOn battery pack, which can charge without a BMS.
  3. Another reason mentioned was the LiOn batteries can fail without warning. The LA battery is more predictable. LiOn batteries also stop working at certain (cold) temperatures. So having a Lead Acid back-up battery running the critical background software helps. Plus, this battery can also warm the main LiOn pack back to optimum operating / charging temperatures.
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Old 9th March 2020, 13:11   #28
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Re: Some technical questions on Electric Vehicles

Noob Alert!

I am a novice when it comes to battery mechanism and IC engines. However I have seen batteries performing weird when exposed to Sub-Zero temperatures.
I have experienced this first hand when on a visit to Shimla my friends car wouldn't start when parked overnight and had to be jumped. My XUV-500 too started in the 2nd go (Battery was 1 year old).

I have seen Electric buses in Manali but those wouldn't be parked for long and are run daily.
I assume the chemical process of the battery slows down due to the temperature.
How EV manufacturers are dealing with this situation? Just curious.
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Old 9th March 2020, 14:55   #29
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Re: Some technical questions on Electric Vehicles

1. One of the major reasons why 12V battery (or even the 12V bus itself) is present in the bus is the legacy 12V systems.

2. 12V has been the standard for past so many years and entire vehicle electricals (i.e. lamps, relays, fuses etc.) and electronics (i.e. semiconductors) have evolved around it.

3. Since EE components are in production, available easily and prices have pretty much settled down, OEMs have no incentive to develop new 48V or higher voltage based systems for auxiliaries. Plus, they can just use proven parts from their existing parts bin by having a 12V battery with DC-DC converter on board.

4. Higher voltage systems do have advantages over the 12V bus when it comes to saving copper and in turn, reducing the weight and cost. For a proper EV that translates into smaller battery -> even lesser weight -> less cost or same battery -> more range. But unless there is an industry-wide shift to higher voltage systems, we shall continue to see good old lead acid batteries in vehicles.

5. This may happen sooner or later as pure ICE based vehicles are also slowly giving way to hybrids. Even a mild hybrid has a 48V battery on board which can be upsized to power heavy duty loads like the AC compressor and EPAS.

Last edited by Rudra Sen : 9th March 2020 at 14:57. Reason: Line space added for better reading
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Old 9th March 2020, 15:54   #30
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Re: Some technical questions on Electric Vehicles

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Originally Posted by pgsagar View Post
1. Charge Retention. This is not to confuse with battery degradation which happens over a period of years. By charge retention over a period of unused time, what I mean is, if I charge up my EV 100 per cent, leave on a vacation for 15 days the very next minute and when I return on 16 th day and turn on the engine, what would be the status of charge in battery? Will it be 100 per cent or would it have lost some of it even when car was unused. This happens in cell phones. I have a second cell phone which I do not use much. If I full-charge that cell phone and immediately turn off for 7 days and turn it back on on 8th day, I find 25-30 per cent of charge lost, even though the phone had remained turned off all through the week. And this, in a brand new phone. Do EV batteries also behave this way?
Doing this might be harmful for your phone's battery. I don't know which brand's phone you use but Apple clearly states that when storing a phone, the battery should be charged only till 50%, neither 100% nor zero. I assume this rule will remain true for other brands as well. Granted this article talks about 'long term', but since you are seeing around 30% drop when you restart after 7 or more days, I believe it will be best if you charge it only till 50% while storing.

Can anyone please clarify if EV batteries should also be half charged when the car will remain unused for a long time?
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