[Sparky88]

I'd like some feedback from knowledgeable Volt owners on this idea for long term storage, and ideas to add if possible.
If someone wants to do long term storage they could buy an inverter, hook it up to the 12v DC to DC converter. Then have a smart 12v charger plugged into that and hooked up to the battery. This way the 12v battery will always be charged correctly. So all the 12v protection systems for the HV drive battery will work. Have the HV battery at 1/3 charge and have it charged only on a weekend schedule. This way the HV battery will have its heating or cooling circuits active.

 

[JuneBug]

OK, so you want to attach an inverter to the DC-DC converter, taking 12 VDC and converting it to 120 VAC to power a battery charger? The only problem is the output of the DC-DC converter is wired DIRECTLY to the 12V battery. So you would essentially be trying to make the 12V battery charge itself. But, by going through the inverter you incur losses by converting 12 VDC to 120 VAC and then back to 12 VDC. It simply isn't going to work.

Instead, plug the smart battery charger (or trickle charger) into a 120 VAC outlet, and connect it to the 12V battery. That would work.

 

[Sparky88]

I was thinking more that the vehicle was at an airport or offsite storage facility. But you wouldn't have the weekend charge available. So just have the HV drive battery full up. At a trickle charge rate I'm sure the drive battery would last quite awhile.

 

[RePo]

Since we're trying to engineer a charge-yourself battery setup, lets simplify it a little. Instead of taking 12V battery and using an inverter to step up to 120V AC and using a trickle charger to take that 120v back to to 12v DC, how about just connecting the 12v battery to itself. That could be done with just jumper cables, and just use one end of them. There wouldn't be any conversion losses, and the battery would hold it's charge for weeks like that.

If you want to use the traction battery to charge the 12v, could do that by leaving the car on.

 

[KNI]

How about putting an on/off plug outlet with mechanical week clock to a wall plug and plugging your charger cord into that? Let's say that every Monday you give the car a good 30mins charge up and then let it sit for rest of the week.

Now if the electricity fails, the mechanical clock will pick up from where it left when the electricity is back up..

I don't know, might be too simple solution.

 

[J.Smith]

I don't even understand what you're trying to do. Put the 12V battery on a trickle charger permanently. Charge the HV battery to 60%. Voila, you're done. Lithium batteries should hold a charge for a very long time, particularly if you keep it in the 40-60% range where their self-discharge rate is low, so by the time you're back it should likely still be above 40% and since its a Volt, you don't need the battery topped off and can just fuel up the vehicle. In fact, I'd be more concerned about fuel stabilizer in the fuel tank since the ethanol in the gasoline is more likely to make it go bad than the lithium battery being a problem.

 

[Sparky88]

The issue I think most people have is the 12v battery going dead and therefore the 12v systems that keep the drive battery in the correct temp range if the OAT is hot or cold during outside storage.

 

[FI Spyder]

The issue I think most people have is the 12v battery going dead and therefore the 12v systems that keep the drive battery in the correct temp range if the OAT is hot or cold during outside storage.

Not sure how the 12V supplies heat or cooling to the main battery or it would be drained in no time. The 12V should be good for a month as it goes into power reduced mode after a short time (minutes). For longer than a month as per Chevy's instructions you want to put it in "storage mode" where it goes to sleep. In cold weather the voltage of the 12V battery goes down and may not start the computers, especially if it is toward the used up side.

 

[KNI]

Not sure how the 12V supplies heat or cooling to the main battery or it would be drained in no time. The 12V should be good for a month as it goes into power reduced mode after a short time (minutes). For longer than a month as per Chevy's instructions you want to put it in "storage mode" where it goes to sleep. In cold weather the voltage of the 12V battery goes down and may not start the computers, especially if it is toward the used up side.

12V supplies power to the control circuit which makes the decision on heating/cooling the battery. When the 12V is out those safety functions are off-line. Unfortunately someone decided that the 12V battery is only charged from the main battery when the car is on, thus the 12V can go out way before the main battery. You'd probably need a year to do that tho.

Other ways (than putting the car on) to charge the 12V battery include some gimmicky 12V charging platform or plugging the car to an outlet (charging disabled after full charge, until either car is powered on, plug is taken out and put back in or electricity goes out and comes back (hence the plug-clock from your local hardware store suggestion)).

edit: correct term seems to be timer outlet or sumthing.. Amazon.com : 110v timer

 

[Sparky88]

That's why a 12v battery charger is needed that is hooked up to an inverter in the car. Am I way out to lunch here? The 366v drive battery would stay charged way longer than the 12v battery. If the 12v battery dies all the 12v system goes with it.

 

[DShields11]

My 2013 Volt is only driven in the winter, from late October through April. When I put it into summer storage I leave it with half a charge in the traction battery and I hook up an inexpensive battery maintainer to the 12 volt battery jumper terminals under the hood on the left side firewall. This keeps the 12 volt battery topped up. This works fine for my car.

 

[Sparky88]

My 2013 Volt is only driven in the winter, from late October through April. When I put it into summer storage I leave it with half a charge in the traction battery and I hook up an inexpensive battery maintainer to the 12 volt battery jumper terminals under the hood on the left side firewall. This keeps the 12 volt battery topped up. This works fine for my car.

So 6mths of storage. Sounds like the simplest method. Thanks for all your responses.