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Discussion Starter #1
I read about people charging to 80% or some other level and I understand why some choose to do so to limit battery degradation, but not how. Is there a setting somewhere that will stop the charging at a preset point? I just started using the supplied 120v charge supply and will be getting a 240v evse at some point. The VW owners manual is not very helpful. Thanks!
 

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You can either use your app or set it on the car directly. Either way you'll need to set a 'charging location' where you set the maximum charge level and assign that location to a charging schedule
 

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Discussion Starter #3
I did finally get to the delayed charge menu and see how that function can work. I haven’t gotten the app and I’m not sure if I will yet. Is there a way to see the real time charge rate? I see the miles available go up and a time that I assume is the time remaining left to charge. I’d like to see a current flow rate or Kw/hr rate if that’s available. I’m just using the 120v charge adapter at the moment.

As for 240v EVSEs, does anyone have experience with the Siemens VersiCharge? That one, along with juice box and clipper creek seem to get good reviews. The Siemens is cheaper, and the button select for delayed charging looks convenient. Thoughts?
 

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There is no way to see the charge rate (watts or typically, kW (kilowatts)) in the car. If you have a 3rd party app like OBDElven, you can see the charge rate. Of course, if you are connected to a public station (either DC or AC), you should be able to see the charge rate on that station or associated app. If your included trickle cable is 12 amps, then your charge rate is approximately 1.4 kW and if it is 10 amps, it is approximately 1.2 kW (120V x 10amps = 1200 watts = 1.2 kW): look at the sticker on your 120V EVSE to find the amperage.

No experience with Siemens products. You might want to find out whether it "plays" well with the e-Golf if you try to control the charging session from the EVSE. I have only used charge timers from the e-manager for either 120V or 240V AC charging and have had no issues.

Best of luck in your choice for the 240V EVSE!
 

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Discussion Starter #5
I used a programmed charge last night with my 120v charge cord and have a basic question. I set the max charge to 80% which is what many seem to recommend. If I set a departure time and the charge level hasn’t been reached yet, will the charge continue or does it turn off at that time? And has there been any more study of limiting max charge to 80%? I’ve read lots of conflicting info, as well as thoughts on VW already programming in an “unusable buffer” to protect the battery.
 

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The charging will continue until the car's battery pack hits the programmed SoC.

No need to study more - there is plenty of data indicating you damage the battery when you keep at 100% "real" SoC, although if you live somewhere where it doesn't get too hot, it is less of a concern. Real is in quotes because as you have indicated, VW, as do all manufacturers (Tesla has smaller top and bottom buffers than other manufacturers), has a top and bottom buffer so you can't access the full capacity of the pack. That being said, the pack is probably least stressed at 50% SoC, so if you don't need to charge to 100% indicated SoC every day, then a 80% or even 70% limit will add useful life to your battery pack. A key difference with the e-golf is that it has no active thermal management, so the car can not actively cool the pack if it gets too hot. Other than the Leaf, most other EVs have active thermal management for the battery pack. With all this being said, I believe VW was very conservative with the pack design and made a good choice in the battery chemistry so that the vast majority of e-Golf packs will not lose more than 30% net capacity by the end of the warranty period. Still, I want to lose as little range as possible so the car can continue to serve all my need for 10 to 15 years.
 

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The key thing is what is your plan for the day.. If you're not planning to go far then don't charge to 100% SoC.. But if you are planning to go far then by all means charge to full.

This is specially true if you have easy access to a L2 charging station that you can use in case you have some unplanned trip.
 

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Completely agree. Charge to 100% and leave soon after so the pack doesn’t sit at a full charge for days or even hours, especially if ambient temps are above ~30 C.
 

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I have done some internet research and I found numerous articles advocating for charging to 70-80% instead of 100% to maintain battery health. In particular there are several articles advocating to not use the DC fast charge if you can avoid it. The onboard charging manager does a good job of managing the charge level. I love that I can heat the cabin on house power before I leave in the morning. If you want to monitor charging events you will need to acquire a charging device that will provide you real time charging rates and status. I have a Juicebox Pro40 and it does a nice job of providing a whole host of information about each charging event. It claims to have some functionality to control starting and stopping of the charge event, but there is no communication between the Car and the charger, so the charger has no idea of the SOC percentage. I have chosen to let the car control the event and use the Juicebox to log charging information. I am really happy with the setup. The only downside that I see is that Enel X (juicebox manufacturer) is hosting the information. The juicebox is in constant communication with Enel X and does not hold any data on board. It therefore needs access to your home wifi. Enel X has not asked me to pay any subscription fee for this service. At least not yet. Had I known that this is how it worked, perhaps I might have gone a different route, but it is working really well.
 

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Yes, if you want to minimize pack degradation, operate at shallow DoD and keep pack between 30% and 70% SoC daily. Right now due to reduced driving, I set the charge limit to 60% and recharge at about 25% to 30% SoC.
 
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