Battery Tender Charging "Full" Battery

Hey guys,

I bought a Battery Tender brand charger (1.25 amp I think) and I decided to use it a bit since I haven't been driving my Charger as much lately (so much work and home projects). I noticed that after I drive the car and park it, if I hook the charger up, it will charge for 12-18 hours before it reads full.

This is after a 25 minute drive or so with the ammeter indicating the battery is topped off (centered). Alt voltage is ~14.5V running.

Granted this is a trickle charger but is this "normal"? Can the charger top off the battery more than the normal charging cycle of the alternator?

Battery is a 2 year old Interstate - not a cheap one either. Otherwise battery and charging system seem healthy. Fires right up and she spins like a top.

That's very normal. It's got to go through its program before you get the steady green light.

Thank you, sir. I have zero experience with these. My last charger was one my grandfather gave me and built in the 60's (still works) and was a bit less complicated not to mention it can dump 30 amps or so into the battery.

Yes it is normal. Driving around for that short time is just a surface charge. I leave my Battery Tender on ALL the time when I don't drive it.

Same Here !!

Not me. I have heard too many stories of garages burning down from these trickle chargers. Heck, I even disconnect my cables from my batteries if I am not driving the car everyday such as my nice weather crusing cars. Not on the daily drivers.

with stock output rates alt on car, that can be pretty much normal it happens. Stock alts barelly can hold the batt fully charged

I use a battery tender junior and switch it between cars every so often. Maybe once a month to fully charge and then I remove it. It works just as you described after driving.

I've had them go bad where I have the green light but only 10 volts..Also the other way around where it's "charging" constantly when there's no need...I ended up trying another brand the battery tender is just too expensive to be replacing every 5 years or so...

For $50, it is good insurance and quality product. If it fails in 5 yrs, that's only $10/yr. I use the Battery Tender on my Cuda. Ctek is another good one. I use that one for my generator battery.
My first Batt Tender lasted 7 yrs. On my 2nd one now, going on 4yrs. Much better then buying a battery every 2 yrs like I did before w/o the BT. My Turbostart agm red cap battery still working great since 2010 using the BT. I don't know if Turbostart is still making them. I have no experience with the other makes of red cap batteries.

I have a Jr. on my bike. I gave $21 for it at Batteries +. I used to get 2 seasons out of a battery, the one in the bike now is 5 years old. Yes, it goes through it's cycle every time I plug the bike back in.

The one I purchased from Tractor store ( led lights) is rotated between my 3 cars and motorcycle.. $25 four years ago??

Handiest device I have ever purchased..