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car battery chargers

PeterT

Ultra Member
Premium Member
Soliciting thoughts from you auto experts. I'm pretty sure my sons truck has a slow short somewhere, we have gone through a battery per year the past 3 years. It doesn't help matters that its been very cold he doesn't start it every 2 weeks, but I wont air my family laundry. I used to boost but getting less keen about that. AMA is booked until July-2024 (kidding but seems that way). Anyways I'm thinking a charger might be worthwhile.
There are many new fangled digital products out there but reading the reviews, not all of them are great. Some don't like charging in cold, which is typically when you need them. Some claim certain amp capability but people say inflated numbers. And I read some chargers just say no & blink error if battery level is too low. But then they plug in a different brand & away it charges which makes me wonder if its a safety thing or charger limitation.

- any recs of what to get or what to avoid?
- is it possible to buy too much amp delivery? More amps = less charging time but for example 75A charger output but safe/recommended 12V rate shouldn't exceed 50A? (just making up numbers I have no idea)
- why is 24v a thing, do them mean like RV battery use or the charging voltage can go up from nominal 12?

I was looking for old school manual switch & needle meter style like this for example
https://www.homedepot.ca/product/lincoln-electric-55a-century-charger-10-2-55a-/1000721724

What about these styles? Am I interpreting correct its a 30A charger but you click to 100A boost & try to start off that like cables to another car battery?
https://www.amazon.ca/Schumacher-SC...ds=12v+battery+charger&qid=1613269767&sr=8-16
 
Charging DC batteries is a complicated subject. I spend hours researching DC charging system design when I had my sailboat which relied on two group 27 deep cycle AGM batters for lights etc and one group 24 'starter' battery for starting the diesel.
DC batteries take a charge quickly at the beginning of a charge cycle but can take hours to become fully charged.
More amps does not necessarily = faster charging time because there is a limit to how much and how fast the battery can accept.
Too much, too quickly can cause damage to the battery.
And a battery that is too low, say 11v or less will likely not accept a charge.
DC-Fast-Charging-Curve_2.webp

(https://www.chargepoint.com/blog/how-dc-fast-charging-really-works-and-intro-charging-curves/)
 
Is a low amp battery maintainer style charger a possibility? That means it is plugged in all the time. They provide a small trickle charge (1-2 amps) and most have an over charge protection. I have "permanently" mounted battery maintainer charger style under the hood of vehicles. I like to trickle charge the battery when I need to plug the block heater in.

Another option that might work is a solar charger system.

I have both of the above types on batteries that do mostly sitting and like both styles in their appropriate applications.

A low charged battery ( or dead battery) is very hard on the life of a battery.

I think all modern vehicles have a low amperage draw at all times ( computers, clocks, etc) but I would expect a healthy battery would maintain that draw for at least a month or more. Cold weather dramatically reduces a batteries potential.

Yes you can overcharge a battery with both amps and time.

I have a battery charger that does 6, 12, 18 and 24 volt. I had read several years ago that 12 volt systems in vehicles were going to fade away as the modern electronics required more power....I don't see any evidence of that happening yet ????
 
I got this one 7 ish years ago at Costco thought it was a bit gimmicky , how ever is the best I have had yet in my experience,
It does not have a start feature, but has a maintenance function for weathered batteries!
It works fantastic has
2a ,6a ,10a, 12a , 15a
Charging I have always used the 2amp charge
Anyways that’s my 25cents worth
 

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A battery a year???? How are you determining that the batteries are bad?

That week of -26/30C caught up with you eh? I ended up having to boost my truck (with my 75amp boost charger) on Friday and it had only sat for a day without being started. Block heater was on a 4 hour cycle timer.

I think it's time for a new battery on that one it's 10 years old now:p

Smart chargers with boost only boost if it determines the engine is cranking. How it determines that I haven't a clue.
 
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I have 4 or 5 chargers, including a big one on wheels. I like the Optima intelligent one the best, but is is expensive. The big manual ones let you also boost, which is nice—but you do need to babysit them and they can destroy a battery if left unattended. It is true that the newer "smart" chargers can be too smart and refuse to charge if the battery is too low. You can trick it by adding a second battery (almost at charge) in parallel for a while.

WRT the actual problem, you need to do a load test on the battery (meters available at Princess Auto) and have the alternator checked at a shop. You used to be able to test the diodes on them yourself, but this is difficult now. Also possible the vehicle has a fault that is drawing power; those are a PIA to trace.

If you are in a bind Peter, I can loan you my large charger and load test meter. Let me know. A temporary solution is a small inexpensive battery tender that trickle charges the battery and keeps it topped up. There are even solar versions. I have both; if you want more info let me know.
 
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This is not a comment about chargers (as I don’t know enough about them), but rather about an “operational procedure” we have employed since we had the same battery discharge trouble.

We have 3 vehicles that don’t see regular use. We adopted the strategy of disconnecting the negative terminal of the battery after use if the vehicle won’t be used within 2 days. As part of the pre-trip walk around, we reconnect the battery. Takes only 30 sec. All problems went away.
 
This is not a comment about chargers (as I don’t know enough about them), but rather about an “operational procedure” we have employed since we had the same battery discharge trouble.

We have 3 vehicles that don’t see regular use. We adopted the strategy of disconnecting the negative terminal of the battery after use if the vehicle won’t be used within 2 days. As part of the pre-trip walk around, we reconnect the battery. Takes only 30 sec. All problems went away.
That is an option provided power is not needed for any security systems, door, clock/trunk/hood locks. I have a vehicle that the back hatch won't open without power.
A convenient alternative to removing negative terminal is a battery disconnect switch. They also work as a theft deterent device. https://www.canadiantire.ca/en/pdp/motomaster-quick-disconnect-battery-terminal-0113507p.html
 
Peter

That first one you linked from Home Depot don't do long term charging worth a damn, You'll usually cook the transformer in them.

Battery tenders are a better option, one that puts out more than the draw while parked or as suggested above a battery disconnect.

Today's vehicles suck amps like mad moving down the road

Check out ProjectFarm on YouTube for some good charger reviews.
 
Peter

Does your son’s truck happen to be a Ford product??

Why do you ask that?

We have a 2011 F150 that does weird stuff when the temp dips low, like anti-theft going off when we attempt to remote start.
 
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Asking because the problem sounds a lot like a problem I had with a seldom used Explorer. After replacing countless batteries over 20 years it turned out to be a faulty battery saver relay. It turns out that many Ford products use a battery saver relay to limit power consumption after a set period (around 30 min). A faulty relay will allow a high parasitic drain. The best I could do was 2 weeks without starting - otherwise the battery charge was too low to start the vehicle. A simple check of the parasitic draw will tell if the relay is the problem. Connect an amp meter in series with the negative terminal and monitor the draw. Since the relay is controlled by the GEM you’ll have to wait for the GEM to turn off the relay (about 30 min) to get a true value of the parasitic draw. There’s plenty of info on the web but I could’t find out if other vehicle brands use this system.
 
Was just perusing CT for a battery and came across this....

APPLICATON NOTES - Vehicle computer system must be reset and battery registered using scan tool.

What does that mean????
 
Thanks for the good info.
Yes, 2002 Ford 150 Lariat. Interesting about the relay
I never thought of a terminal disconnect, good idea there.
Its on charge now, neighbor had one. We'll see if it takes tomorrow AM.
I suspect if the voltage drifts to low/flat, its not healthy for chemistry.
 
Don't cheap out on a charger. The less expensive ones don't last more than 5 years. I'm on my 3rd or 4th one now.
 
I have an older version of this one.

https://www.canadiantire.ca/en/pdp/...y-charger-with-80a-engine-start-0111979p.html

I got on a battery charger kick a few years ago when I was playing with microcontrollers and wanted to build my own smart charger. I learned a bit about the charging theories but at the end of the day, I ended up buying that one and it has been great. I figured no use in reinventing the wheel. It is a large step up from the old transformer based chargers, although they still serve a purpose.

I installed a battery maintainer, as suggested above, on an aerial ladder at work several years ago. We had new radios installed and the radios would not transmit if the battery was below a certain value, which was higher than what the battery typically sat at. The get around was to start the ladder in the station after a failed radio check. So every morning, radio check would fail for that unit. After the maintainer was installed, no more problems. So I think a maintainer is a good resolve, if you need to. Firetrucks are plugged in to keep the air pressure up anyways so it was just matter of mounting the charger somewhere and routing the wires in a way that throwing helmets and gear into the cab would not break a connection. The truck was due to be replaced and the mechanics did not want to put new batteries into it (or spend much time or money on it if we did not have to) A trickle charger is a band aid though, imho. Vehicles should be able to sit for months and not require boosting. As suggested, there could be an excessive draw somewhere but I think unlikely unless something is not working properly. If the summer time, water in a light socket but this time of year.....:confused: You say son....has anyone installed stereo equipment or accessories? If they were installed to connect before the accessory option on the ignition switch, then maybe the parasitic drain from those are changing the original electical needs of the truck. But again, a check of vehicle off, load check, might reveal this.

It could also be a bad connection somewhere so that when your battery gets to the point where it is not delivering 110% of what is considered a good battery ie >1 year, the bad connection robs your starter system of having enough energy to turn it over. The connection can be a cable connector end (any fuzzy stuff on them?), a weak solenoid or the contacts in it, weak starter, etc.

As suggested, have your battery tested. Canadian tire will do this for free for you. Is it the right size battery for that vehicle? Say it was replaced with a slightly small one years ago, and then each year, you take it in and ask for a replacement. Each year, buying a small one. The excessive load on a "too small" battery will cause it to become weak over time too.

I am a GM guy so would love to bash Fords, but then this thread would divert away from the original question...:eek: But seriously, a 2002 Ford truck should not be eating batteries like that. I doubt it is an excessive draw (but it could be. Some good answers as to troubleshoot for that have been posted.)

I lean towards connections, or electrical components in the starting system/charging system.

Good luck!
Cheers,
Shawno
 
Was just perusing CT for a battery and came across this....

APPLICATON NOTES - Vehicle computer system must be reset and battery registered using scan tool.

What does that mean????
I had 2011 F150 that I was told by the "stealership" that the computer had to be told that I put in a new battery for the charging system to work properly. I was so flabbergasted at the stupidity of such a requirement. I replaced the battery myself and I do believe I had some sort of charging system code show for a short time but things fixed themselves in short order and were fine as long as I owned the truck. I never did any sort of reset.
 
I had 2011 F150 that I was told by the "stealership" that the computer had to be told that I put in a new battery for the charging system to work properly. I was so flabbergasted at the stupidity of such a requirement. I replaced the battery myself and I do believe I had some sort of charging system code show for a short time but things fixed themselves in short order and were fine as long as I owned the truck. I never did any sort of reset.
That's so interesting. I think that may be because some onboard computer systems track and report maintenance, so they may remind you when it is time to test your battery and/or replace it (like some vehicles tell you % Oil Life remaining). Car batteries generally need replacement every 5 years.

While on the topic...some (but not all) of the error codes and reset issues (clocks, radio stations, seat positions, etc.) can be persevered on some vehicles with those cheap 9V battery change maintainers. They are just a small 9V battery clip that plugs into your power port (i.e., cigarette lighter) and trickles enough juice temporally to maintain your computer's registers while changing the battery. The fly in the ointment is that many vehicles have a diode inline with these ports now so you can't push power back in to them anymore. It's not easy determining if your vehicle has one or not. Some are hardwired right behind the port, but others are on the computer board where you'll never trace it. I just use another battery in parallel somewhere to be safe; you just have to remember that when handling the cables during hook up.

Looking back on what I just wrote I realize I said, "fly in the ointment." This is like a Progressive Insurance Commercial. I've turned into my parents.
 
Car batteries generally need replacement every 5 years.
While this is generally true for cars and light trucks, I don’t get the same lifespan in the big truck. I’ve gotten in the habit of changing them every fall. It’s right around $200-220 for all four batteries once the cores are returned, I consider it cheap insurance for the winter.
I should probably change the two in my little F350 this year, they’re getting up there. One is around 4 years old the other one who knows how old.
 
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