Are you charging batteries on your DD?

[BMWTurboDzl]

Originally Posted by MCompact
I have a BMW branded C-TEK maintainer I use on my Club Sport; everything else is driven enough to keep the batteries charged.



Do you remember what BMW recommended with regards to when you should use a tender? Because I had only driven my care twice of since March I ordered a CTEK but had to cancel because I was able to take my car out for a 30 mile drive.


You think a 30 mile drive once a month is enough for a 6 yr old battery?

 

[meep]

Just posted this on another thread: My f150 has does the mpg thing where battery charging is reduced to save a few points of mpg. A few years ago I put a fairly sizeable flexible panel on the camper shell... it feeds .9 amps in full sun at 13.8 volts, don't recall the wattage. It's about 3' x 1', glued down with silicone and screwed at the four corners. It's about 2mm thick so most folks don't even notice it. On the average day, the charge controller shuts it down about 3 hours after getting to work. If you you are just looking for a maintainer, I'd think 1sq ft panel, as long as it's not the single-sheet-of-glass type, would be fine. Those square glass sheet types are less than half as efficient (powerful) as real PV cells.

Truck starts quickly every day with a 5-6 year old battery. I'd do it to the car if there was a way to make it look ok.

My wife is required to drive in daily. For a while I was doing top-off charges on her crv every 6 weeks or so. The battery failed early within warranty. Not sure that strategy helped.

 

[meep]

Originally Posted by BMWTurboDzl
Originally Posted by MCompact
I have a BMW branded C-TEK maintainer I use on my Club Sport; everything else is driven enough to keep the batteries charged.


You think a 30 mile drive once a month is enough for a 6 yr old battery?


Probably not. It will get a decent bulk charge and maybe some absorption but certainly not finishing. A flooded cell can self discharge in 30 days. An AGM will last longer, but the vehicle is still pulling on it to maintain electronic memory. It's pretty impressive actually, to me, that the vehicle starts on its own. 3 weeks and the *nal retentive in me would have it on a charger for a few hours.

M

 

[faltic]

Yes the amount of driving for me has really been curtailed lately. I try to top the charge off on everything every couple of weeks.

 

[JHZR2]

My low use cars sit on battery minders as much as I can anyway.

The other cars get a top up when I think about it. I had the van battery fail from a shorted cell a few months back. I have to think that sitting and cycling caused that.

 

[yugrus]

I swear I read somewhere that you shouldn't charge the battery if the ambient temperature is above 20C (heat kills). If true, perhaps this is why batteries go bad in the first place, it's quite warm under the hood? I have my onboard NOCO trickle charger (no temperature compensation) on timer to go during the night only, in the summer. I assume it's safe to charge all day (and night) long in the winter? Even if it's -20C outside?

 

[dblshock]

I run a Coleman 3W solar charger on the boat 24/7 as it sits on the dock all summer, handy.

 

[GJM120]

Originally Posted by BMWTurboDzl
Originally Posted by MCompact
I have a BMW branded C-TEK maintainer I use on my Club Sport; everything else is driven enough to keep the batteries charged.



Do you remember what BMW recommended with regards to when you should use a tender? Because I had only driven my care twice of since March I ordered a CTEK but had to cancel because I was able to take my car out for a 30 mile drive.


You think a 30 mile drive once a month is enough for a 6 yr old battery?



If your car is someplace where a charger is practical, like a garage, I'd put it on a good charger/maintainer like Battery Tender or CTEK.

If my car (128i) is going to sit for 3+ days, I hook up the charger. It's so easy with the jump terminals under the hood. A side benefit is it gets me in the habit of looking for any problems like oil leaks.

 

[Kiwi_ME]

My EV charges the 12V battery automatically for 20 minutes every 24 hours when not driven. And over 5 weeks I think the main battery didn't even drop 1%.

 

[R1jake]

I've never had any luck using a maintainer, once in a while I'll do a top off charge and this has worked best for me.

 

[BMWTurboDzl]

Originally Posted by GJM120
Originally Posted by BMWTurboDzl
Originally Posted by MCompact
I have a BMW branded C-TEK maintainer I use on my Club Sport; everything else is driven enough to keep the batteries charged.



Do you remember what BMW recommended with regards to when you should use a tender? Because I had only driven my care twice of since March I ordered a CTEK but had to cancel because I was able to take my car out for a 30 mile drive.


You think a 30 mile drive once a month is enough for a 6 yr old battery?



If your car is someplace where a charger is practical, like a garage, I'd put it on a good charger/maintainer like Battery Tender or CTEK.

If my car (128i) is going to sit for 3+ days, I hook up the charger. It's so easy with the jump terminals under the hood. A side benefit is it gets me in the habit of looking for any problems like oil leaks.



Ya. I bought a CTEK. With CTEK at least It's essentially idiot proof.

 

[GJM120]

The fact that good maintainers - like CTEK - switch to a float mode, I don't think you can hurt a battery by connecting it pretty often.