Short trips - kill battery?

[Jackphom]

I commute to work now and worked from home before, so lots of the time before hand I would just drive maybe a few miles a week here and there. Now, I drive 20 miles to work and have to move my car 3-4 times a day due to parking and wanted to know, will I eventually run down and kill my battery?

I have a cobb accessport in my MK7 GTI that I can watch the voltage, when it's cold out. It hovers pretty high (14.7-8), resting voltage is somewhere around 12.1-2 when I turn the car off.

I think the alternator may be on it's way out from the heat, during the summer time I am seeing it struggle to maintain 12.8-13 voltages in 80s/90s.

 

[dadto2]

I think your current situation is easier on the battery than your work from home situation. When the car only driven a few miles per week, you probably didn't run it long enough to recover from the parasitic draw while sitting. Now you get plenty of charging time.

 

[slybunda]

I noticed having a battery bag seems to be good for batteries lifespan

 

[Dave9]

No short trips won't kill the battery unless you have a charging system problem, or starting problem whether due to starter, cable corrosion, very cold temperatures requiring extended crank times, etc. pulling a lot more than normal out of the battery with each start.

You could very well have a charging system or battery problem if not both, as a battery in good condition would not drop as low as 12.1V right after turning the vehicle off - should be higher than that unless you are measuring with all kinds of electrical/electronics circuits still live, drawing significant current.

I don't think your alternator is on the way out from heat if it has managed to keep the same battery going until now, entering winter. More likely the battery is dying, how old is it? That in itself is a strain on an alternator which could eventually kill it but it would typically stay same or get worse, not improve with cooler weather. You're only in NJ, not a very hot climate.

Based on seeing a charge system voltage of 14.n and then 12.1-12.2V when the vehicle turns off, that in the context of a 20 mi commute, I'd replace the battery before the worst of winter comes, or if it's not very old, put a charger on it to see what voltage it gets to and with it disconnected from the vehicle, see what voltage it settles to after 1/2hr off the charger. If it's still down around 12.2V then it's not holding the charge well.

 

[dishdude]

No, that 20 mile drive to and from work will more than charge it up.

 

[meep]

Your warm temp voltages are fine. For a long time now cars reduce voltage when it’s hot because the battery doesn’t need as much voltage to charge - some vehicles have a temp sensor in the battery tray. In addition, current battery management tech is more strategic on how to charge and will often stay lower than that under cruise … my ford sat at 12.4 in the moderate seasons unless I was coasting or braking.

 

[edyvw]

Your 20mls commute mitigates potential issues resulting from moving car in parking lot.

 

[KrisZ]

I don’t know what others are smoking but a 12.2-12.1 resting voltage means you almost killed your battery already. Clearly your short trips and moving the vehicle constantly has killed this battery. It must be a pretty big one though to not cause starting issues yet.

 

[Thermo1223]

I commute to work now and worked from home before, so lots of the time before hand I would just drive maybe a few miles a week here and there. Now, I drive 20 miles to work and have to move my car 3-4 times a day due to parking and wanted to know, will I eventually run down and kill my battery?

I have a cobb accessport in my MK7 GTI that I can watch the voltage, when it's cold out. It hovers pretty high (14.7-8), resting voltage is somewhere around 12.1-2 when I turn the car off.

I think the alternator may be on it's way out from the heat, during the summer time I am seeing it struggle to maintain 12.8-13 voltages in 80s/90s.

Yes it will raise the voltage to wake the cold battery up. Your alternator is fine, the BMS will not overcharge and trend to undercharge the battery in the summer to preserve it's life in the heat.

There is a current sensor to track the draw on the power system & battery. I wouldn't worry about it until you need too. The Tiguan's battery gave us 3 years which with Start-stop active seems on par.

 

[Donald]

Recent cars with electronic ignition and fuel injection start almost immediately. The amount of charging to charge up the battery from the starting load is minimal.