Anyone top-off charging a lead-acid battery as part of regular maintenance?

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Does anyone do this?

I bought a battery charger, used it on a car that short-trips 90% of the time (under 15 min from start to off).

2.5 year old battery from the Mazda factory on a CX5 with 25,000 miles (made by Panasonic which gets bad feedback from the Mazda forums)

First time starting up, I was pleasantly surprised at the difference that it made. Bonus: the CX5 must use a small SSD as my settings weren't erased.

Am I imagining things? Why isn't Scotty telling everyone who short-trips to get a charger?

Supposedly for lead-acid batteries, recharging to 100% extends its lifespan.
 
Occasionally on my TR6 as the stock ~35a (maybe...) alternator will not keep up w/ demand if I use headlights and heater and drive at moderate RPM... The manual instructs this also. That said, you should not have to do this with a healthy modern car unless you are at the extreme end of short tripping.

What does the manual say?
 
With my older cars/batteries I will remove the caps and if I see the plates are not Black/Grey/Black/Grey. They are more Grey-Grey. In other words they are becoming sulfated. I will trickle charge the battery for a couple of days [topping up water as necessary] and the plates tend to de-sulphate and return to Balck/Grey/Balck/Grey. Get a few more years out of the battery this way. I leave the battery connected to the car when charging.

This takes the car out of service for a couple of days but sometimes I have to much time on my hands.
 
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The Panasonic battery in my Lexus lasted over 9 years before needing a replacement and it had never been topped off with a charger nor a maintainer.

However, I do keep our daily drivers on a maintainer when ever possible, which is quite often. And if the batteries have removal caps(which are lead acid), my preference, I also keep the acid level topped up.
 
When my 'auto start / stop' stops shutting the engine OFF (at 76% charged),
I will hook up my Battery Tender overnight and charge it back up.
 
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Does everyone who tops up their battery leave the battery connected to the car, or do you disconnect the negative terminal?
 
Regular? No. Irregular? Yes. My f150 only sees a 5 mile loop on the weekend for trash-dump duty and I'm not convinced it's getting fully charged. So I'll throw a charger on to see if it "takes it", but only if it's been a couple of months of not taking longer trips.

Truck has an upgraded "3G" alternator and delivers 14.x volts all the time as God intended. If I had a newer thing with a fuel saver alt I'd do so more often.
 
I have a CTEK smart charger. I will use that a couple times per year normally on a weekend when I know I can hook up at night and remove next day. Batteries stay in the car hooked up CTEK, NOCO and others have the extra pigtail you can hook up so it's a simple plug in, no clamps.

I kind of "listen" if it starts cranking slower for when needed but also have one of the digital clamp on ones that @Donald said was a conductance not capacitance battery tester. Either way it seems to work well for my needs and gives CCA's/Volts that correspond to my slow cranking or normal cranking
 
I bought a 70$ 24F at Wal-Mart to keep my son's 533-i alive , but then the 7yr old battery in the Rat died. I don't think it liked being swapped back into an E-28. I used a HF 1/2 amp maintainer at whim to make it last that long. 24F is Camry sized with a 1 yr warranty. The new battery is loose but topped off.
 
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No, but my vehicles tend to get mostly longer drives. I should do this on our CRV as that tends to get just 15 minute drives, so it does see some short trips like that.

My lawn tractor battery, now that I should be doing that more often. It rotates between mower and ATV. Thing is, the ATV has a better starter and will start & run when it won't start the mower. But I think the ATV actually charges the battery better, go figure. I just figure that battery will never last more than a few years.

Truck has an upgraded "3G" alternator and delivers 14.x volts all the time as God intended. If I had a newer thing with a fuel saver alt I'd do so more often.
Indeed. I consider this "smart" charging to be complete nonsense. Car should charge a battery up in the same manner as getting the engine up to temp: as fast as possible, and then keeping it there. Optimum state for both entities.
 
I have a CTEK smart charger. I will use that a couple times per year normally on a weekend when I know I can hook up at night and remove next day. Batteries stay in the car hooked up CTEK, NOCO and others have the extra pigtail you can hook up so it's a simple plug in, no clamps.

I kind of "listen" if it starts cranking slower for when needed but also have one of the digital clamp on ones that @Donald said was a conductance not capacitance battery tester. Either way it seems to work well for my needs and gives CCA's/Volts that correspond to my slow cranking or normal cranking
My concern is some battery chargers and maintainers have desulfation circuits that put pulses of electricity into the battery. In an attempt to knock off sulfur crystals back into solution. While fine with the battery disconnected not sure it's great for the vehicle electronics to have these pulses of electricity come into the circuit.

For my truck I would need to separate the two batteries by disconnecting one. That's a hassle for routine maintenance.
 
Get in the habit of turning the headlights on.
I think my kids, as a rule, turn on the headlights. If that was taught in driver's ed, then that's what they do.

Coming into the time of year where the lights are on more often than not.

But not a bad idea, all around.
 
Does anyone do this?

I bought a battery charger, used it on a car that short-trips 90% of the time (under 15 min from start to off).

2.5 year old battery from the Mazda factory on a CX5 with 25,000 miles (made by Panasonic which gets bad feedback from the Mazda forums)

First time starting up, I was pleasantly surprised at the difference that it made. Bonus: the CX5 must use a small SSD as my settings weren't erased.

Am I imagining things? Why isn't Scotty telling everyone who short-trips to get a charger?

Supposedly for lead-acid batteries, recharging to 100% extends its lifespan.
I do it at least every weekend on my work truck. It spends a lot of time with key on engine off and doors being opened like 20-40+ times a day so it slowly gets drained down, especially with the smart charging logic (even though it's a 2005 Silverado).

I don't have to worry about getting a random dead battery which seems to happen from time to time on our company fleet.
 
I think my kids, as a rule, turn on the headlights. If that was taught in driver's ed, then that's what they do.

Coming into the time of year where the lights are on more often than not.

But not a bad idea, all around.
Was taught that by young drivers 25 years ago. Plus I used to ride a motorcycle. Better visibility is always good. I also adjust my position in the lane when it will help sometime trying to turn left in the other direction to see me. That was in the motorcycle training course but should be something everyone does IMO.
 
Was taught that by young drivers 25 years ago. Plus I used to ride a motorcycle. Better visibility is always good. I also adjust my position in the lane when it will help sometime trying to turn left in the other direction to see me. That was in the motorcycle training course but should be something everyone does IMO.
I recall my second vehicle was a Subaru. It had headlights that were connected to the ignition switch, and would turn off if I took out the key. For a while I just left the lights on. Then burned out two headlights in short succession. End of that. [I was in high school and looking back, head lights weren't that expensive, but that was my thinking then.]

Too long ago to remember what I was taught in school regarding headlights. Probably wise to teach people to just turn them on, the roads are full of idiots driving today with no lights on in the rain, fog, or dark.
 
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