Plug In Question (Prime)

The device that comes with the car plugs into the car and into a standard 120V AC outlet on the other end. You only need something special if you want to charge at Level 2 (240V).

 

you should have a reasonably modern outlet, either dedicated to the car only, or else with nothing else on it, running at the same time you're charging.

 

...grounded 3-prong plug I assume?

 

correct.

 

The Prime is listed as taking 5.5hrs to charge from a standard outlet. In the case that the outlet is on a circuit in use elsewhere, the charge amperage can be lowered. This means longer charge time, but not enough to not fully charge charge the car from when a it gets home to when needed the next day for most people.

 

How can it be lowered, and by how much?

 

Whether real or imagined, I sense that repeated quick charging is hard on the battery and 'might' impact long-term battery life.
Question - Over several years, would slow charging at 120v be less damaging on the battery that 240v?

 

Slower is better but both are actually very slow (less than 1/2C).

Being hot and fully charged or being drained totally dead are the two big things that hurt these batteries. I doubt Toyota will let them be fully charged (4.2V per cell) so they've already doubled their cycle life by limiting them to 4.1V per cell. Not leaving them there for long will enhance battery longevity quite a lot and the electronic charge schedule seems designed to do exactly that. To get them to be totally dead, you'd have to drain Ev mode and then leave the car to self discharge for something like a year.

 

OK, thought of a (maybe) dumb question. Is there a standard for the plug configuration on the car to enable the use of all public charging stations? Or are some public charging stations more standard than others?
I suspect that Tesla's supercharger network is not available to Prime for any amount, but I could be wrong. Just don't know.

 

That rate is slow by what some systems use. For example, the CAHdeMO option is much faster.

The often overlooked impact you have direct influence over is cold-soak, allowing time for the battery to rest prior to recharging it. The timer is handy for that.

 

All but Tesla should work okay.

 

Level-2 is that standard (oridnary 240-volt charging) for public chargers. Leaf has a connector for it, but also offers CHAdeMO (like Prime in Japan). Tesla has an adapter available for it. CCS is the other high-speed type. Since both require higher voltage lines and deliver more amps, they are much less common. Level-2 is quite capable and the backward-compatible plug is an obvious benefit. That's why most of the automakers offer that.

Level-1 is supported by the normal household outlet in your garage. Most people will simply use that 120-volt connection for the slower charging overnight. The size of the battery-pack accomodates it well, a fact overlooked when considering the capacity. You just plug & play.

Prius PHV (Toyota's first plug-in hybrid) offered a great opportunity for real-world study. The limited rollout into select areas spread across just enough owners to figure out what really was needed. That's vital information when attempting to deliver a configuration capable of competing directly with traditional offering. That meant keeping costs low, but not sacrificing ability.

Watch for reports from new owners about how well Toyota targeted Prime. And of course, keep asking questions. There's nothing dumb when it comes to entering an entirely new market. People have to start the discovery process somehow.

 

One of my friends has owned a Leaf for the last three years, and he told me it has never been plugged into anything but 120V. Despite its much larger battery and the fact that he doesn't charge it every day, he says over night is sufficient for a full or almost full charge every time he charges it.

This makes sense. 12A corresponds to probably about 1.2kWh usable per hour on charge, including losses. If you put it on charge at 6 and take it off charge a 7 the next morning, that's 13 hours or 15.6kWh net available over just one night on just 12A at 120V.

 

No experience myself. Comments from PiP and Volt owners say the amperage can be dropped to 8amps, and that might even be the default.

The charging standards are broken down into 4 groups; it used to just be 3.

AC level 1 is the slowest, and done from a basic, 15amp home outlet. AC level 2 is faster by working with higher voltages and amperages, and this is what people are talking about when installing a home charger. These can be hard wired or plug in. The plug used in North America is referred to as a J1772. That is the open source SAE standard for EV charging protocols. The EVSE charger, either level 1 that comes with the car or level 2 mounted on the wall, isn't actually the charger. That is built into the car, and its rating is the top limit on the car's AC charging rate. The EVSE itself is there to tell the car how much electricity it can provide.

That J1772 is used by every plug in sold here, and is used by all the public AC chargers.

For those looking at the Prime in the US, that is all you really need to know.

Going beyond AC charging is DC charging, which is much faster. This used to be referred to as level 3, and the level 1 and 2 didn't have the AC prefix, but it is officially DC level 1 and DC level 2. Why? I'm not really sure, since the DC charging out there now is the faster DC level 2. The big difference between DC and AC charging, besides whether using alternating or direct current, is that DC charging doesn't use the car's onboard charger. The charger is truly the charger, which means the upper charging speed is limited by it and not the car. It is fast up 80% of the battery's capacity, then it quickly slows down to prevent damage to the battery. AC charging follows the same protocol, but with a charge time measured in hours, it isn't likely to have impact on trip planning.

There are 3 global standards for DC charging, plus one for China. The most well known is Tesla's Supercharger. The patents are open, but no one has opted to buy into Tesla's charging network. CHAdeMO was developed in Japan, and is common in some areas by being around the longest. It uses a plug separate from the AC charge one. The Prime in Japan has it, and it can be seen in some photos. CCS was jointly developed between a German and American group. It is referred to as the Frankenplug because it an extension to the J1772 AC charge plug.

There are discussions here and elsewhere on which DC standard is better, and why we even have different ones to begin with. For those looking at a plug in hybrid in Canada or the US, it doesn't matter. The Supercharger network is the best one now and for the near future for those that want a BEV for long trips. It is more extensive and better laid out than the other two, and while the CHAdeMO and CCS standards could match Supercharger in terms of charge rate, the ones actually installed are around half the speed.

There are discussions here and elsewhere

 

The one supplied with the PiP does not have this function AFAIK. Third parties' ones may have it (or not)
My portable EVSE is a LEAF one which originally was a L1, but was upgraded by EVSE Upgrade - Low-Cost EV Charging Solutions to:
Automatic detecting dual voltage 120/240VAC.
Programmable 6-25A in 1A increments. I use it (set to 8A) when plugging into unknown and suspicious outlet in opportunity charging.
Worth mention: the higher grade third party EVSEs have some protection against wall outlet warming-up due to a bad connection or other reasons, they run thermistor wires to the plug (outlet side) as temp detectors.

 

i can't change the amperage on my oem evse, and i don't recall that being reported for prime, but don't know for sure. whatever volt has won't apply.

 

Sounded like the amp setting was set from the car, at least with the Volt. It defaulted to 8 or 9 amps, but you could program the car to use 12amps when it was at home, instead of setting it each time.