Don't worry, the car will take care of itself. Just make sure it's securely plugged in (and don't forget to push in the slider on the Tesla plug!).
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shrink
Member
Wow. 20%? That seems really low. I'm no expert, but I thought I read somewhere that 50% SOC is the healthiest state for long-term Li-ion battery storage. Ah, well, I'm sure Tesla engineers know what they're doing.
A follow up question RE: storage mode. I live in Phoenix and it gets crazy hot here. Will the TMS run whenever needed in storage mode? I think we had a high 1 or 2 weeks ago of a lovely 118 F.
djp
Model 3 Performance
Here are the degradation rates for Li-ion NCA cells at various temperatures and states of charge. A 20% SOC is better for storage with the battery lasting 50 years (at room temperature) before losing 20% capacity. At 50% SOC it takes about 27 years to lose 20% capacity.
The BMS will try to keep the battery temperature below 105F even in Storage mode, but at low states of charge the temperature doesn't matter as much.
http://www.nrel.gov/docs/fy12osti/53817.pdf
Much to my surprise, my car only lost 20 ideal miles in 16 days of inactivity. I thought it was supposed to lose energy more quickly than that? I had the car plugged in and set to storage mode. The ideal charge went from 172 to 152 miles during that 16 day period. That amounts to 1.25 miles per day or less than one percent per day. Hmm?
djp
Model 3 Performance
That sounds about right. The vampire drain on the Roadster is extremely low and most of the losses are from self-discharge of the battery. The self-discharge is fast at high SOC but slows down as the SOC drops.
There are signs that this crappy long winter is finally starting to wane. I put my Roadster into Storage Mode about a month earlier than ever before, and I don't think I'll be pulling it out of the garage for another month. Looks like it'll be in Storage Mode for five months!
Here's a curious observation. I peek at the Roadster VDS every day after plugging in the Model S. Until recently it would bounce back and forth between 30 km and 34 km (plus the hidden reserve of about 30 km). Suddenly about a week ago this changed and it now bounces around between 26 and 29. Was slightly alarmed the first time 26 appeared so I checked that the car was still drawing power okay. It was.
Any thoughts? I'm thinking maybe the pack is slowly going out of balance, and it's reporting that?
Here's a curious observation. I peek at the Roadster VDS every day after plugging in the Model S. Until recently it would bounce back and forth between 30 km and 34 km (plus the hidden reserve of about 30 km). Suddenly about a week ago this changed and it now bounces around between 26 and 29. Was slightly alarmed the first time 26 appeared so I checked that the car was still drawing power okay. It was.
Any thoughts? I'm thinking maybe the pack is slowly going out of balance, and it's reporting that?
I'm guessing you're out of balance but not sure. This winter has been so darn cold that my Roadster blew the fuse to its battery heater! Fortunately it's easy to replace. The ranger bought the new fuse at Radio Shack. -5 F last night and expected to be -8 tonight! It's late March and we still have 2ft of snow on the ground???
My ideal range was holding strong at 192 down to 185 over three years. It was in Storage mode for a few months, upon recharge, ideal was down to 168 and estimated... 80.
After a mild panic, I switched to standard for a week or so and it's back to 175 ideal even though the battery is still cold. I'm hoping that after some driving it'll start to report back to normal.
After a mild panic, I switched to standard for a week or so and it's back to 175 ideal even though the battery is still cold. I'm hoping that after some driving it'll start to report back to normal.
djp
Model 3 Performance
I'm not sure how the BMS would know the pack was out of balance at low SOC. It's also interesting that my Roadster bottoms out at 64km in Storage mode. It's been in storage for less time than yours, but it's topping up nightly (see spike at 3am).
wiztecy
Active Member
Interesting. Can you verify the Roadster is waking up from sleep and checking on the state of the ESS? Honestly I'd personally pump some charge into that pack if I had it in storage mode for any long duration of time, such as multi month winter storage. From all my research the pack optimum SOC is at 40-50% SOC for storage or sitting in any idle state where its not being used. And your at 14% SOC approx. I'm curious what Tesla spec'd the (time) duration of Storage Mode to be and don't know if they even thought about Roadsters sleeping for so long.
I always put my Roadster in Storage Mode with 60-70% SOC in it before I leave for a 1-2 week trip. That way it has enough to gobble up for its pump, wake up, and random brain activities. I use storage mode to just keep an eye on things and take care of things in case of an emergency, but truly I want it to be where I want it to be.
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The other day I pressed the Charge Now button, and it added 1 km.
i might take it out of storage mode and see what it does. I think the seemingly never-ending winter may be finally throwing in the towel. It snowed today, but then it rained. I'll probably be putting it back on the road sometime next month anyway.
i might take it out of storage mode and see what it does. I think the seemingly never-ending winter may be finally throwing in the towel. It snowed today, but then it rained. I'll probably be putting it back on the road sometime next month anyway.
wiztecy
Active Member
"Panasonic Lithium Ion Battery Storage: The batteries should be stored at room temperature, charged to about 30 to 50% of capacity. We recommend that the batteries be charged about once per year to prevent overdischarge."
http://www.powerstream.com/Storage.htm
"The best battery manufacturers store lithium batteries at around 60 degrees and at a 40% charge level."
5 Best Storage and Charging Tips for Extending Lifespan Of Lithium Ion Batteries in Home, Business | Battery Blog by ZeusBatteryProducts.com
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Curious if OVMS can interact with Storage mode or at least override it, so that instead of Tesla managing the SOC that OVMS can. That way you can say I want to keep the ESS at a 40-50% SOC, and if it drops below that target, pump in some AMPS. I think there's a setting in OVMS to charge to a set SOC but I don't think there's any daily wake up call that works like storage mode does.
http://www.powerstream.com/Storage.htm
"The best battery manufacturers store lithium batteries at around 60 degrees and at a 40% charge level."
5 Best Storage and Charging Tips for Extending Lifespan Of Lithium Ion Batteries in Home, Business | Battery Blog by ZeusBatteryProducts.com
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Curious if OVMS can interact with Storage mode or at least override it, so that instead of Tesla managing the SOC that OVMS can. That way you can say I want to keep the ESS at a 40-50% SOC, and if it drops below that target, pump in some AMPS. I think there's a setting in OVMS to charge to a set SOC but I don't think there's any daily wake up call that works like storage mode does.
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djp
Model 3 Performance
I'm down to 58km now, but the BMS still wakes up nightly and draws 5kW for five minutes to top up.
I'm not too worried about it, lower is better for storage. The recommendations to store at 30-50% SOC assume the batteries aren't on a BMS so include an allowance for self-discharge. It's fine to store lower, as long as the BMS doesn't let it go to absolute zero.
I'm not too worried about it, lower is better for storage. The recommendations to store at 30-50% SOC assume the batteries aren't on a BMS so include an allowance for self-discharge. It's fine to store lower, as long as the BMS doesn't let it go to absolute zero.
wiztecy
Active Member
That makes sense and having the BMS management. I was picking that up, that the long term storage at 40-50% mainly was to keep the cell from over-discharging. Also that Panasonic said to store them at room temp, which from research and the battery professor video, I got the impression that lower colder temps were better for the cells in storage. I believe the latter (colder) is better
I guess for me, I liked having a little bit more in the tank just in case a breaker went off. But if you have OVMS and a neighbor who you can share the location of your spare key and back-up charger location you should be fine.
@djp - I'm assuming this is the same TED that your using:
Amazon.com: TED The Energy Detective Electricity Monitor TED1001: Home Improvement
How do you like it?
I just find it odd that it sat in a narrow range for a long time, then suddenly started creeping downwards.
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