davepl

I have a C6 Z06 that often goes several weeks without being driven, and if I'm unable to keep a float charger on it for whatever reason, it'll run the battery dead (no additional electronics, been that way since new).

I'm on my third battery because of this, as most starting batteries do not like to be deep cycled. I know you -can- use a deep cycle battery if you upsize the capacity, but not sure if it's worth.

Besides "hey dummy, keep a charger on it", any suggestions? I don't know if Optimas are more tolerant of this (and they seem to be a love it or hate it battery), but am willing to try it if so...

8VETTE7

Should probably post this in the C6 section and not the C5.

If anything Optimas are lesss tolerant of not being on a battery tender. When they discharge they seldom recover properly when you try to recharge them.

had2have-it

I would check to see if it has a higher than normal electrical load, (short, device drain down, etc). 78 series battery or larger and if it sits for several weeks you are going to need to find out how to trickle the battery. I am not a fan of Optima batteries or other optima type batteries. You could put a higher capacity battery by modifying the tray to allow for the larger dimensions.

dndrsn

I charge the battery and disconnect the neg cable when I know it's going to be sitting for over a couple weeks.

9020v

Just get any spec battery and unplug the negative when not in use for more than a few weeks.

Jnape

Park it in reverse. I know it sounds stupid, but many years c6 had this recommended. Worth a try.

jrose7004

Wow, a C6 Z post in C5 Tech! I am honored!

Chicago1

hey dummy well if you know its gonna sit put a trickle on it instead of buying 3 batteries. Harbor freight has them for like 5 bucks. I assume you car is in storage/garage or someting for all that time so just plug the chargr in an outlet. Ps wrong section

duramaxsky

If you have no place to plug it in try a solar charger. They are made by a number of companys. Battery tender makes one. Also you can pay less at an RV store or Harbor Freight. Just make sure you get one with a regulator. If not it will cook your battery. Some cheap one don't have them some do. A small one should handle the small draw on the car. The C6 must draw more than most cars. My C5 and Sky sit for up to a month in the winter and always start. And the C5 has had a weak battery since I got it. 30 mins with the radio and it wont start. The Sky is an 08 and sat on the hoist for over 2 months as we had a bad winter . It has the original battery and started right up. The few nice days we had I just drove the Vette as it was no the bottom and not worth switching them for 1 nice day.

duramaxsky

I have the cheap Harbor freight ones on all my tractors and my diesel generator. They always start with old batteries and the generator sits over a year sometimes. the lawn tractor sits all winter and my backhoe sits until I need it. Sometimes several months.

oldmansan

It's cheaper to buy a battery tender than to replace batteries. You also get to run a lighter battery. I use the same battery tender on my C6 and Lotus Exige S when needed. I've saved over 20 pounds of weight as well. Seems like a no-brainer for a performance car.

San

Andy 53

I'm using a Sears DieHard Platinum on my 2005 base coupe. It is normally driven once each weekend but often goes 2 weeks between starts. On several occassions, it has gone three weeks without starting. It starts every time and has never shown any weakness when starting. I do not run a trickle charger on the battery. The battery is about 2 years old now. It comes with an 8 year warranty. The first 4 years are with free replacement. The last 4 years are pro-rated. If you can't run a trickle charger, this might be what you need. The battery is expensive though...about $200!

Andy

AU N EGL

battery Tender works

StKnoWhere

Or use a Priority Start, it automatically disconnects the battery if the battery voltage drops to a level too low to start the car. Make sure you have a way to get into the car with the battery disconnected (that the rear hatch key works, the hood is unlatched or press the unlock button for 5 seconds to leave the door unlocked).

Jnape

Is this a C6 thing? What is the exact function? (just saw this tread was moved fron C5.....)

StKnoWhere

PriorityStart is for all automotive applications, check out the link:

http://www.prioritystart.com/

foremaw

AORoads

if for some reason you can't put a batt. maintainer on it, that solar thing with a shutoff so as not to over charge sounds like an idea. everything else in the way of batteries starts getting up toward and over $200, like Optima, DieHard Platinum and Odyssey batteries. but the last two mentioned are supposedly excellent. you can ask cthusker about the Odysseys since he uses them.

Rebel 1

what i do

0Optima Bill

Hi Dave,
If I may, let me add a few thoughts here.
First, any modern car that sits for any period of time without being cranked or driven will unfortunately succumb to a discharged battery. They have so many small amperage draws on them that you never notice if you drive it daily or even weekly. However, if they sit, those small draws discharge any battery below its designed operating range. Optima batteries have lower internal resistance than traditional flooded lead-acid (FLA) batteries, which allows them to provide current well beyond their specified ratings. However, if you leave them connected to a draw, they will continue providing current for far longer than a FLA battery. They are more resilient to deep discharges than FLA batteries, but they make take longer to recharge, if they are discharged to a greater extent.

According to their website, the PriorityStart unit has a disconnect threshold set by the factory at 11.7 volts (about 75% discharged).* That means this unit will allow your battery to discharge down to 11.7 volts, before it disconnects any undesired drain on your battery.* We recommend batteries always maintain at least 12.4 volts (about 20% discharged).* When voltage drops below this level, sulfation begins to occur, which will reduce a battery’s performance and lifespan.* PriorityStart’s website also indicates their unit uses approximately 9 to 12 milliamps, which by itself is a very low draw, but if the battery is already discharged to 11.7 volts, this certainly doesn’t help the situation. *

PriorityStart’s troubleshooting guide also suggests starting a vehicle every 60-90 days and running it for about 15 minutes, although they do not specify if that means running it at idle in a driveway or driving it on a road.* We often hear of people starting their stored vehicles and letting them run at idle for 10-15 minutes, with the idea that this activity recharges their battery.* The opposite may actually be occurring, as idling a vehicle may not allow an alternator to replace the energy that was used to start it.* Repeating this process over the winter months can eventually lead to a discharged battery.

Using a microprocessor controlled battery maintainer or tender on stored vehicles will help extend the life of any battery.* If access to an electrical source is limited, parking your vehicle with a fully-charged and disconnected battery is also a viable option, as is removing the battery and keeping it maintained in your home during the winter.* This video offers some good suggestions on proper battery storage-** Good luck with your decision for a new battery and if you ever have any battery-related questions in the future, please don’t hesitate to contact me.

Bill Howell
eCare Manager, OPTIMA Batteries, Inc.
www.powerpacknation.com