I've recently had a problem with my 2018 Prime where it takes a long time to start charging, specifically to connect the HV contactor, start drawing power, and provide an estimated time remaining. Steps: 1. Park and turn off the car 1a. No schedule is set, and I don't select the Charge Now option. 2. Plug in a Chargepoint cable 3. The light below the charging port turn solid green within a few seconds and stays solid The next steps normally happen within 10-30 seconds, but now are occasionally taking 3 minutes: 4. HV contactor clicks 5. Power reported on the chargepoint station ramps up to ~3.2kw 6. The car gives me an estimated time remaining When this is delayed, the chargepoint station reports just 0.01kw. The AC-DC converter seems to be active powering a fan somewhere in the backseat, and Hybrid Assistant shows the 12V battery voltage at 13.0V. At around minute 3, I hear the contactor click and charging actually starts. I can't remember if any of the blue lights are on during the 3 minutes, I forgot to check. So far I've only had this happen twice, both times at Chargepoint stations at work. I've had issues with some of these stations in the past where the light never turns green because the station and the car can't communicate for whatever reason. There are two "good" stations I always use with newer cables and electronics that don't have that problem. I don't think it's a problem on the station side, but I can't rule it out. I haven't seen it with my home charger, but I've had very limited access to home charging for some of the past few months. I don't think it's anything environmental. Temperature today is 45F, and the battery temperature is about the same. Even when the battery is below freezing it normally starts charging right away, and just runs the battery heaters in parallel. It sat for a few hours before I drove 2 minutes to the charger and plugged in, so it's not a battery power limit or anything. The battery was at 8% this time and probably similar last time. Any ideas what could be causing this or if it indicates some other problem? I had the 12V battery die on me shortly after last time this happened, so I wonder if that's related? Maybe the car has to make sure the 12V battery is charged sufficiently before it connects the HV battery? I have not replaced the 12V battery yet, but I also haven't had subsequent 12V issues.
More than likely the issue is with the Charge Point station. The Prius are a relatively slow charger, when compared to full EVs. The other issue may be your pack being too warm - Needs to cool, so initial charge starts off slow, so it doesn't damage the pack. As the pack cools down, the current ramps up. What's the cost to charge your Prime at a Charge Point? I've never found it cost effective, unless it's free and those plugs are usually beat to heck.... Some stations, I just drive away from, than risk damaging my socket.
It's a level 2 station at work. The cost is basically the same as electricity at home, $0.13/kWh. I'll pay up to around $0.20 but above that isn't worth it. Free is always nice, but those are becoming rare. The worst is ones that charge by the hour, since the Prius Prime is relatively slow to charge. At 3.3kW I'm paying effectively 2-3x as much for a given amount of energy as someone charging a real EV at 6-9kW. I used the exact same charger today, with almost identical conditions, and it started charging right away. Even when the battery it hot it still starts doing something right away, although power ramps up and down a bit as it goes through the battery cooling cycle. But it's been 45 degrees F the past few days, and the battery is about the same temperature. It is well within the comfortable range where it doesn't need to throttle charging for being too cold or too warm.
If you don't have window visors on the car, I'd suggest getting them. I always keep all my windows down about 1/8-1/4 inch to let the pack breath, since it's pulling cooling air from the cabin. You may also want to give your socket pins a gentle push, to make sure they're still firmly in place. There's been reports that those pins can dislodge and slide back when plugged-in - causing intermittent contact and charging. The dangers of using a public charge station; abused connectors.
