lagodue

I have a Porsche battery maintainer on my Carrera which seems to work fine. When I went to the dealer to get another one for the Jeep Trailhawk he advised for storage longer than a month I should not be using the maintainer as it does not monitor the battery charge and could possibly "overcharge" the battery and kill it. Is this possible?

He advised getting the more expensive charger/maintainer as it would monitor and vary the charging as required for storage longer than one month, and avoid "overcharging."

Any informed opinions out there?

kromdom

DISCLAIMER: I am not a battery charging expert.

The charger your dealer is describing sounds like what my trusted DELTRAN battery tender does: http://www.batterytender.com/Automot...derR-Plus.html

I have been using these for decades now and have had zero problems with overheating or overcharging

P.S. I thought the Porsche branded units also did the same?

Nedster

That's the one that's hooked to my battery for five months at a time, no issues. One year i didn't use it, i had to replace the battery.

dporto

** Also not an "expert" ** I did just buy a "Battery Tender" brand charger/maintainer. I can't speak for the others mentioned, but the "battery tender" brand includes "smart circuitry" that reads the connected battery and only charges when needed - they will not overcharge the connected batteries.

Hurdigurdiman

Just a little advice. Completely lock the car for storage, as it takes less charge from the battery when fully locked than it does to keep the car unlocked. If the horn beeps when locking, then something is still opened.

pfbz

A at $25 shipped will do exactly what you want. I can't imagine the Porsche maintainer doesn't have a float/maintain mode that would also work but obviously much more expensive.

The dealer is sort of right, leaving a battery on a conventional charger for long periods will kill the battery, but that's not what the Porsche maintainer is.

If you want to learn about charging modes, look here.

lingpoen

2nd the above post...little trickle charger works on Harley, Ford, Porsche, and Malaysian Scooter with NO probolems ever-

NOT A BATTERY EXPERT

lingpoen

make that "NO PROBLEMS" ever....

DER951

JEGS has Deltran a Battery Tender Jr. for $20 shipped

http://www.jegs.com/i/Battery+Tender...=20150129email

pfbz

Just checked that out... Jegs has 'free shipping' but a $4.99 'handling' fee. lol. Amazon free 2-day shipping for the win!

lagodue

After hearing that the Porsche maintainer might overcharge the battery and kill it, I found this at Sears for $30 - versus Porsche equivalent for $130. (On sale today for $20)
Comes with 3 attachment options, including my much-preferred cigarette lighter plug-in.

Ahsai

If you have a Porsche charger similar to this , your dealer is giving you BS.

The Porsche charger is a CTEK rebranded (CTEK is much cheaper) and both are intelligent chargers that have sophisticated logic to charge and maintain the battery and can be connected to the battery indefinitely without hurting the battery, unless the unit itself is defective. Once the battery is charged, it will go into the lower voltage monitor mode and then send pulses to the battery from time to time to check if the battery needs further charging.

5CHN3LL

The advice from your dealer would make sense if you were using an old-school battery charger with trickle-charge mode. If you have a maintainer - as others have indicated - the dealer is on crack.

lagodue

This is the charger they said might fry the battery as it ain't smart enough to know when to stop tricklin' - they said ok to use for a month or so, but not long term. Long term use the CTEK or equivalent = Diehard

Spokayman

That looks like one of the two units I am using for my cars.
I've used it now for five years, months at a time in the winter.
Never had a problem.
You can see when this unit is giving juice to the battery and when it isn't by the illuminated red LED. By my observation, most of the time the LED is out indicating no charging.
If you don't have a manual with the unit, look up information on the internet using the model number and see whether it is a true maintainer or whether it is just a charger.