Why are OBC's so limited?

OBC = On-Board Chargers, the device that transforms AC do DC for your battery.

I live in a part of the world with very few DC Fast Chargers, but a decent number of Type 2 chargers with 22 kW, because Type 2 is much cheaper to implement (200 EUR for me).

Many popular EVs have very small OBC, limited in different ways:
- maximum kW
- just one AC phase

I have a Nissan Leaf 2018 (40 kWh) and my Type 2 port is limited to just one AC phase and 6.6 kW.
The paradox for me (living in Europe) is that in order to have 6.6 kW, I must usually have 3 Phase 22 kWh installation (32A).

The Renault Zoe has no DC fast port but can use 22kW on Type 2 connection with the internal OBC!

So, why de OBC limitation? Is a question of price? Weight? Or just plain step-by-step feature release?

You've got some unit confusion. See https://mynissanleaf.com/viewtopic.php?p=389317#p389317.

Ricoseu said:

Many popular EVs have very small OBC, limited in different ways:
- maximum kW/h

Click to expand...

kW/h makes no sense. You mean kW?

Ricoseu said:

I have a Nissan Leaf 2018 (40 kWh) and my Type 2 port is limited to just one AC phase and 6.6 kWh.
The paradox for me (living in Europe) is that in order to have 6.6 kW, I must usually have 3 Phase 22 kWh installation (32A).

Click to expand...

You mean 6.6 kW and 22 kW?

Ricoseu said:

The Renault Zoe has no DC fast port but can use 22kWh on Type 2 connection with the internal OBC!

Click to expand...

You mean kW?

Obviously, you're outside the US. For AC charging, we don't have 3-phase charging for any mass market consumer EVs. We use J1772 and not Mennekes Type 2 here. I'm guessing that Nissan developed the Leaf to be geared more towards J1772 charging in North America and Japan. Seems like J1772 is limited to 80 amps and can't do 3 phase. Most public J1772 EVSEs are 30 amps at max. Most folks don't buy home J1772 EVSEs beyond 30 or 32 amps.

Renault left the US market decades ago. The closest thing we have to them in the US are Nissans.

Yes, I've edited the post.

So, the big question is why are so limited (3.3 kW on older Leaf, 6.6 kW and one Phase gen 2).
It seems to be an artificial limitation, as Type 2 (AC charging) stations are much cheaper and easy to find than DC.

Even is the US, you can use 2 Phases.

In Europe, many new DC stations have only CCS plug for fast charging. CHADEMO is not the future in Europe, but I wish to charge the car faster at work/home, as my installation supports 22kW, but the OBC is limited and I have the example of the Zoe, that is the same car and uses 2 kW on AC.

It seems to me is the simple cost-cutting problem, that makes the EV hard to swallow.

Ricoseu said:

Even is the US, you can use 2 Phases.

Click to expand...

Err, yes, but it's rather different. In the US, there are two phases of 120 V with respect to neutral, 180 degrees apart. So between the two phases you get 240 V. In Europe, you get three phases of 220 or 230 V wrt neutral, 120 degrees apart, giving 380 or 400 V phase to phase.
If you take it as read that you want 200-250 V input to an on-board charger, the choices are 240 V (single phase, the neutral is not useful) in the US, or three sets of 220/230 V in Europe.

In Europe, many new DC stations have only CCS plug for fast charging. CHADEMO is not the future in Europe,

Click to expand...

It's a weird and painful situation for Japan. In Japan, 90% or more of the fast charging stations are CHAdeMO, so all the Japanese vehicles have this port. The world is moving away from CHAdeMO towards CCS, so eventually (many decades from now, perhaps), all those CHAdeMO stations in Japan will have to be decommissioned.

It seems to me is the simple cost-cutting problem, that makes the EV hard to swallow.

Click to expand...

I think the main thing is that vehicle manufacturers would prefer to use the same OBC in all models if at all possible. So for now they do. Maybe if the European market becomes big enough to justify it, or competition forces them to, they'll release European models with higher power OBCs.

Actually, the single phase mania seems to be isolated to North America (USA and Canada), Japan, and a handful of small countries. So really it's not just the "European market" that is affected, it's basically "all of the world except North America and Japan". [ Edit: but also not China; see next post but one. ] I wonder if the whole world will change not just to CCS, but to all type 2 CCS (with only one phase connected in the single phase regions). Just to unify the cabling and EVSEs.

coulomb said:

In Europe, many new DC stations have only CCS plug for fast charging. CHADEMO is not the future in Europe,

Click to expand...

It's a weird and painful situation for Japan. In Japan, 90% or more of the fast charging stations are CHAdeMO, so all the Japanese vehicles have this port. The world is moving away from CHAdeMO towards CCS, so eventually (many decades from now, perhaps), all those CHAdeMO stations in Japan will have to be decommissioned.

Click to expand...

I doubt that'll happen in Japan.

Japan and China are working jointly on a successor to CHAdeMO that combines to replace the Chinese GB/T DC FC standard and CHAdeMO w/a new one called ChaoJi (https://electricrevs.com/2019/06/19/joint-china-and-japan-chaoji-project-works-towards-chademo-3-0/).

cwerdna said:

Japan and China are working jointly on a successor to CHAdeMO...

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Ah! In my rant, I neglected the elephant in the room: China! The Chinese car market has been insulated from the rest of the world for some time, but it looks like that's finally changing, with even Teslas to be sold in China (as long as they are manufactured there).

So what the Chinese do could have a large bearing on how the world standards progress. Unfortunately, it looks like that region (China and Japan) will have yet another standard. At least it should be relatively easy to develop an adapter cable from CHAdeMO to ChaoJi, although if it handles hundreds of amps, it might not be cheap or compact.

Thanks for pointing out my blunder.

US homes also tend to have 200 amp single phase 240v connections to the power grid.

For Nissan not doing a heavier obc than 6.6kw does a few things. Don't need battery cooling as much, the heat put off by the obc is limited, cheaper smaller, fewer parts needed to run 6.6kw single phase.
Plus the big target markets for the leaf use single phase for residential power.

Looks like ChaoJi will use can bus and should be adaptable to chademo.

Ricoseu said:

So, why de OBC limitation? Is a question of price? Weight? Or just plain step-by-step feature release?

Click to expand...

Price.

Higher power OBC costs more to build.

And realistically, not universal demand.
A large fraction of US electric cars use mostly 120V 15A, the standard household outlet. Enough to handle 65 km/ 40 miles of average daily driving with an overnight charge, which is more most people in the USA drive.

Ricoseu said:

Yes, I've edited the post.

So, the big question is why are so limited (3.3 kW on older Leaf, 6.6 kW and one Phase gen 2).
It seems to be an artificial limitation, as Type 2 (AC charging) stations are much cheaper and easy to find than DC.

Even is the US, you can use 2 Phases.

In Europe, many new DC stations have only CCS plug for fast charging. CHADEMO is not the future in Europe, but I wish to charge the car faster at work/home, as my installation supports 22kW, but the OBC is limited and I have the example of the Zoe, that is the same car and uses 2 kW on AC.

It seems to me is the simple cost-cutting problem, that makes the EV hard to swallow.

Click to expand...

Most US homes are 240 VAC single phase. It's extremely difficult to get 3 phase in a home. It's considered "commercial" power and is subject to capacity charges in addition to to actual power used. I know because I tried to do it a few years ago and couldn't convince SDG&E to install it for me. In reality, higher charge rates aren't needed. Most electric cars charge overnight and 6-10 KW is all that's needed for that. Tesla had an option for Dual 11 KW chargers but it was expensive to install and required dedicated wiring. Almost no one bought them and they were eventually dropped as an option. CCS is the future but Nissan is heavily invested in Chadamo and probably won't change.

My home chademo will draw 8.4kw, put out 8.1kw to the car up to around 80% SOC and that's plenty fast enough. I only use it during the winter.
I do most of my charging with a 12 amp 240v evse and that's all I need most of the time.

From my observations it appears that roughly half of EV owners charge at home and only use 120v.
But a large portion of the 120v only people have public charging or can charge at work.