I live in SoCal, the winter weather here in Jan~Feb is mild, lowest temp at 40F~60F at night. The car will be kept in an indoor garage. In the past, I've left my gasoline car in storage for 8 months and all I did was disconnect the battery. But this Prime is almost brand new, so I'd like to take more precaution. Is there even a starter battery to disconnect? Does it matter much about how much gas to have in the tank? Suggestions are appreciated.
For me personally, 2 months is a fairly short period of time. The only two things I might tell you to consider would be putting the cheapest "12v Battery Tender Jr" on it & leave the main traction battery with a very minimal SoC. (Charge) www.amazon.com/Battery-Tender-021-0123-Junior-Charger/dp/B000CITK8S Rob43
There is an auxiliary (12-volt, lead-acid) battery under the hood. It’s not actually used for starting the engine—this is done with the large HV battery—but it should be maintained just as a starter battery would. I agree with @Rob43: two months isn’t all that long, indoors in a mild climate. Toyota offers a few guidelines in the Owner’s Manual (PDF) on page 96, under “If the vehicle is not used for a long time.” For new vehicles in dealer inventory, Toyota has more involved requirements, given in two service bulletins, T-SB-0009-19, “Long-Term Vehicle Storage Guidelines” (PDF), and T-SB-0006-19 Rev1, “Maintenance for HV and Auxiliary Batteries” (PDF). The car makes an internal record (described in my previous posting) each time it’s left for more than 60 days. For such a short storage period, I don’t think so. You should, of course, follow the general rules to prevent fuel aging (Owner’s Manual, “Notice about fuel,” page 104).
I'm pretty sure Open Road Toyota Port Moody didn't read or head that missive, with our 2010 (build date August 2009), purchase date November, 2010. The car was boxed in, at the back of a shed. Very dusty. A dead bird lay beside it. They did have it running when we arrived for a test drive, to "warm it up for you"... That didn't work out so well: after the test drive we had to back out to check something, maybe the odometer reading. The 12 volt battery was still dead as a doornail. It did clean up nice.
Can you (or anyone else) explain the reason or benefit for leaving the HV battery with a minimal charge during a long term storage? I tried to find any related such info in these Toyota bulletins, “Long-Term Vehicle Storage Guidelines” (PDF), and T-SB-0006-19 Rev1, “Maintenance for HV and Auxiliary Batteries” (PDF), but I couldn't. My Prime just sits for several weeks (7~8 weeks) at a time and I'm wondering whether to have the HV battery charged at minimum or maximum? Currently I leave the HV battery at fully charged (I disconnect/remove the charging cable after fully charged because it's outdoors) and the auxiliary battery connected to a waterproof battery tender during my long term storage.
Roughly ~40% SoC for a single cell Li-ion battery, this thinking would put your traction battery somewhere near "almost" 0%. BU-702: How to Store Batteries – Battery University Rob43
That's for a battery at room temperature. Is the buffer capacity amounts known? Near "0%" might only be 10% to 15% as there is a portion of buffer at the top when fully charged.
The consensus procedure for more than a month is: (for any vehicle with a gas engine) Fill the tank and add the appropriate amount of fuel stabilizer. Might be more important with a Plug-IN if you use the gas slowly anyway. Attach an automatic, smart, tender type charger to the 12 V battery (2 amp capacity or less). Enjoy your vacation, or whatever, and don't worry about it.
Real vs. Nominal Prime Battery Capacity | Page 4 | PriusChat At best, the near zero capacity of the pack is 20%. From the Battery U link, "storing at 3.7V yields amazing longevity for most Li-ion systems." The 40% capacity is suggested because voltage is near that at about 3.8V, and self discharge isn't a concern. That recommendation is based on a battery kept at room temperature(25C/77F). At lower temperatures, the cell voltage will be lower.
TMI. While all of that might be true, the battery pack will be perfectly happy no matter WHERE you leave the SOC......as long as it is in the "normal" operating range......and the down time is only a few months.
Battery tender on 12 volt is good idea..I learned the hard way. Two dealers told me I didn't need one and the 12 volt was dead and you can't even open the traction battery charge door when that happens. The other thing I do is fill the gas tank the non ethanol gas.
