It's actually good that your parents have a 3-phase charger as that may allow them to charge the car quite quickly, although the car needs to be able to use the extra power that is available. I don't know if that's the case for the BYD but you can easily check online.

Don't worry about using the 3-phase charger as all EVs can use this.

Best for battery health is to keep to a minimum the amount of time the battery spends above 80% charge or below 20% charge (as a rough guideline).

If they don't drive many miles, charging to 80%, driving it down to maybe 40% and then refilling to 80% would be good for battery life.

[Edit: Adding this to agree with others that your parents should not use the regular outlet. That is definitely not recommended as a regular practice as it has a higher level of safety risk than using the charger designed for charging cars.]

 

Just want to add a bit of nuance to the 80% portion. As the Dophin has LFP batteries you do want to charge it to 100% on a fairly regular basis, to ensure that the BMS is fully calibrated and the cells are balanced. However, do that when it is intended to be used in the next day or so, especially if it is warm. The reason to do this more often has to do with the way flatter, and smaller differential, voltage curve on LFP batteries. Once the voltage in a cell drops below a certain point the care will go stop, regardless of the voltage on the other cells, this is for lifetime and safety reasons, so you don't want one cell to be much lower in charge than the rest.

 

The granny chargers (thst plug in to a normal 3 pin plug socket) are not designed for regular charging; my daughter used hers daily and it lasted less than four years before failing.

If your parents have a wall charger then they should use that, it’s rapid charging (50kw+ DC chargers) too often that can potentially lead to shorter battery life.

 

To answer the main question: No, charging on AC at 22kW (the 3-phase maximum rate) rather than 7kW doesn't make much difference compared to 100kW DC.

Are you sure your parents have a 3-phase electric supply? It's pretty unusual in the UK.

 

Upwards of £50K for the charger, must have lots of room for the rectifiers, the electrition probably said 3 pin🤣

 

Basically use the charger the electrician installed, doesn't matter if its 7kw or 22kw.

Don't use a granny charger, it's safer to use the installed charger for various reasons and no it doesn't adversely impact the battery more than other types of charging.

Done.

 

This!
The 3 pin charge cable (aka granny charger) is really for occasional use only.

The wall box (EVSE) is designed for the job and does it best and safest. Use that.

And yep battery will be fine. The wall box is still slow by EV standards. The rapid chargers you see at motorway services etc can deliver 10x the power.

We used to worry about the affect of Rapid charging on early cars like the Nissan Leaf (which gets hot when Rapid charging) but your parents BYD is a modern car with active battery cooling so will have no problems with rapid charging. It’s basically history that you don’t need to worry about.
As mentioned it’s better if the car doesn’t sit around at 100% all the time, but even that is not so important as cars have a buffer of battery they don’t use. So even at 100% on the dashboard the battery is not really full to its real capacity - there’s an unused bit of extra margin to protect it.

 

Hi all.

Totally new to EVs.

My parents just got the BYD Dolphin.

An installer installed the supplied charger (mounter on the wall - a gift from BYD).

Unfortunately, while I know ICE jargon, I have no clue what it's called, all I know is that the electrician said it's a "3 phase charger".

On the other hand, there is another regular wall outlet in their garage (the one you would use for your washing machine, let's say), and I did happen to read about how fast charging can degrade the battery.

So to my question:

Given that my parents don't use the car much, and they are totally fine with plugging it in at 16:00 and letting it charge till the next morning (08:00), should they just use the regular wall outlet (and avoid the 3 phase one)?

BYD did supply a regular cable which connects to a regular outlet.

Is that healthier for the battery? My parents tend to keep their cars for many years.

THANK YOU!

No. I think we may be getting terminolgy in knots here. All AC charging be that from a 3pin plug or a standard 32A wallbox or three phase charging is actually slow charging as far as the car is concerned. There's no difference to using that compared to a 3-pin plug, indeed most EV drivers never have the need to plug in on 3pin at all.

The bit about fast charging degrading the battery is actually talking about rapid chargers, sometimes called DC chargers, those big things you find at motorway services. They can be 150kW or more. But even then there's little evidence they do any damage even when a car is charged exclusively with those.

So it is perfectly fine to use the 3-phase charger all the time. Keep the 3pin charger for if the main charger breaks that is the only time you will use it.

Refer to the owners manual for the percentage charge for better battery health often this is 80% - but charging to 100% is completely fine if the intention is to use it.

 

it is perfectly fine to use the 3-phase charger all the time.

This.
It's all you need to know.

A 3 phase home charge point is not NEARLY fast enough to be a problem, and it's questionable whether even DC rapid charging at much higher rates does any damage.

 

The user has a flag from Israel so perhaps they are not located in the UK? Maybe it is common to have domestic 3-phase power there, it is common in Europe except the UK, in which case 11kW AC charging will probably be installed (maybe 22kW but that is rarely supported by the car).

 

Like a previous poster said the Dolphin uses an LFP battery which likes to be charged to 100% so KISS and just leave it to charge to 100% for every charge. From the Dolphin manual

"It is recommended to fully charge the vehicle at a regular basis (at least once a week), and fully charge it from low battery (SOC <10%) once every three to six months."

 

Hi all.

Totally new to EVs.

My parents just got the BYD Dolphin.

An installer installed the supplied charger (mounter on the wall - a gift from BYD).

Unfortunately, while I know ICE jargon, I have no clue what it's called, all I know is that the electrician said it's a "3 phase charger".

On the other hand, there is another regular wall outlet in their garage (the one you would use for your washing machine, let's say), and I did happen to read about how fast charging can degrade the battery.

So to my question:

Given that my parents don't use the car much, and they are totally fine with plugging it in at 16:00 and letting it charge till the next morning (08:00), should they just use the regular wall outlet (and avoid the 3 phase one)?

BYD did supply a regular cable which connects to a regular outlet.

Is that healthier for the battery? My parents tend to keep their cars for many years.

THANK YOU!

Fast charging is charging at a rate that will fill the battery from empty to full in under 1 hour.

At most, the 3 phase charging station can provide 22kW, and the car's charger can only accept 11 kW or less, depending on model.

The BYD Dolphin has a 30kWh battery or larger, depend on model.

At fastest, the car will charge in just under 3 hours, which is NOT fast charging. No battery life issue.