Battery Charger Testing Results

[pasadena_commut]

I’ve got one hooked up to my 2018 right now. I can’t for the life of me figure out why this thing pumps out 14.6 on a fully charged battery for 24 hrs, before it goes into maintenance mode? It’s like this thing is on a timer! Cant be good for a battery.

14.6V is indeed too high for a fully charged battery, at least for an AGM battery. Are you sure the battery was fully charged? For a big battery and a low current charger it can take a long time before it gets to the float stage if it starts from a very discharged state. See the tables here for recommended voltages for charging and float:

https://discoverbattery.com/support...harging-and-what-float-voltage-is-recommended

That charger might have been sitting in the absorption phase at 14.6V, during which time the voltage is constant and the current falls. See the diagram here:

https://lifelinebatteries.com/agm-batteries/

 

[f355spider]

14.6V is indeed too high for a fully charged battery, at least for an AGM battery. Are you sure the battery was fully charged? For a big battery and a low current charger it can take a long time before it gets to the float stage if it starts from a very discharged state. See the tables here for recommended voltages for charging and float:

https://discoverbattery.com/support...harging-and-what-float-voltage-is-recommended

That charger might have been sitting in the absorption phase at 14.6V, during which time the voltage is constant and the current falls. See the diagram here:

https://lifelinebatteries.com/agm-batteries/

The battery is likely fully, or close to fully charged when he started. The Northern Tools/Battery Minder 1 amp Model #12117TC has an strange algorithm, different than their other chargers. It will stay at this higher charging voltage for over 1 day on a fully charged AGM battery by my observation, before reaching float. I called and questioned Battery Minder tech support about this and they said it was normal operation and it will default to float at a maximum of 72 hours. I'm not exactly sure what stage it is in (it claims to have 8 stages in the IFU), and what actual amperage it is putting out at this voltage.

I may try it again this weekend using my bluetooth monitor where I can log the charging process and post it next week. The car I will put it on, has a Battery Minder 2012 AGM on it constantly. I will swap them on Saturday for a couple days to compare the difference again.

It also has a very mild temperature compensation compared to the standard Battery Minder products.

 

[pasadena_commut]

Not sure I would do that experiment on a battery I valued. 14.6V is over the gassing voltage (depending on temperature, as always). If the current measured at that voltage is super low maybe the battery can recombine the gas away, but if not the battery will vent (or swell, maybe both), and that is not something you want an AGM battery to do ever.

 

[f355spider]

Not sure I would do that experiment on a battery I valued. 14.6V is over the gassing voltage (depending on temperature, as always). If the current measured at that voltage is super low maybe the battery can recombine the gas away, but if not the battery will vent (or swell, maybe both), and that is not something you want an AGM battery to do ever.

Its high 30s in my garage, I'm not concerned with the voltage, you shouldn't either ...the temp compensation is so mild it will not even climb much, if at all

 

[Carlostrece]

I’ve got one hooked up to my 2018 right now. I can’t for the life of me figure out why this thing pumps out 14.6 on a fully charged battery for 24 hrs, before it goes into maintenance mode? It’s like this thing is on a timer! Cant be good for a battery.

Batteryminder is the brandname of my smart trickle charger. 1500 is the model name, which means it's max output is 1.5A. My Batteryminder 1500 works well for me, and it's a pulsing charge which it claims has 2 benefits...

Pulsating charging desulfates the battery. It claims. I don't know if it's actually effective at desulfating, but fingers crossed. It charges the battery and that's the main thing.

Pulsating charging does not boil the battery fluid. It claims. Probably true. I don't know.

It's a smart charger that monitors state of charge of battery and ambient air temp, and adjusts the charger output accordingly. It has an automated float mode.

It's $51 at Amazon Prime (free shipping).

 

[D1dad]

Batteryminder is the brandname of my smart trickle charger. 1500 is the model name, which means it's max output is 1.5A. My Batteryminder 1500 works well for me, and it's a pulsing charge which it claims has 2 benefits...

Pulsating charging desulfates the battery. It claims. I don't know if it's actually effective at desulfating, but fingers crossed. It charges the battery and that's the main thing.

Pulsating charging does not boil the battery fluid. It claims. Probably true. I don't know.

It's a smart charger that monitors state of charge of battery and ambient air temp, and adjusts the charger output accordingly. It has an automated float mode.

It's $51 at Amazon Prime (free shipping).

Yeah the 1500 looks like a quality charger, much like the 2012, just a little less amps. If I didn’t already have a whole box full chargers that I don’t use, I’d consider one. I like the walwart idea and was hoping the northern tool would fill the bill, it just didn’t work out. After I unhooked my car and drove for a few hrs yesterday and hooked it back up, my 2012 charged the battery and was maintaining in an hour. The northern tool, would have went 30hrs before float charging would have kicked in. I gave my northern tools away and they were given back. I couldn’t fool my engineer son in law lol.

 

[Carlostrece]

Yeah the 1500 looks like a quality charger, much like the 2012, just a little less amps. If I didn’t already have a whole box full chargers that I don’t use, I’d consider one. I like the walwart idea and was hoping the northern tool would fill the bill, it just didn’t work out. After I unhooked my car and drove for a few hrs yesterday and hooked it back up, my 2012 charged the battery and was maintaining in an hour. The northern tool, would have went 30hrs before float charging would have kicked in. I gave my northern tools away and they were given back. I couldn’t fool my engineer son in law lol.

Umm. You give people gifts that are the junk you don't want? Yikes.

My dad used to do that. Give me his junk in the guise of gifts. For example, when I was a kid he'd eat candy (out of my sight or presence) then later ask me if I wanted candy. Then make a big show of giving me empty wrappers. I learned not to trust him.

You did that with a charger that's worse than worthless because it can ruin car batteries. Your gift could have ruined your son's cars batteries. Your gift was a passive aggressive attempt to sabotage him.

Father of the year award.

 

[D1dad]

Umm. You give people gifts that are the junk you don't want? Yikes.

My dad used to do that. Give me his junk in the guise of gifts. For example, when I was a kid he'd eat candy (out of my sight or presence) then later ask me if I wanted candy. Then make a big show of giving me empty wrappers. I learned not to trust him.

You did that with a charger that's worse than worthless because it can ruin car batteries. Your gift could have ruined your son's cars batteries. Your gift was a passive aggressive attempt to sabotage him.

Father of the year award.

Did I say I gave it as a gift! I gave them to my son in law for his sleds and side by sides and said “try these out and tell me what you think”. I didn’t wrap them up as gifts and give them away. He gave them back and agreed they were crap. Do you just look for posts to comment on to irritate people? They work but they’re just garbage. You’re truly an idiot and how dare you question me as a father! My daughters a nurse practitioner, my middle son employs 9 people and owns a roofing company and went to college on a D1 baseball scholarship while my youngest son is in the navy. No candy wrapppers involved!

 

[f355spider]

The battery is likely fully, or close to fully charged when he started. The Northern Tools/Battery Minder 1 amp Model #12117TC has an strange algorithm, different than their other chargers. It will stay at this higher charging voltage for over 1 day on a fully charged AGM battery by my observation, before reaching float. I called and questioned Battery Minder tech support about this and they said it was normal operation and it will default to float at a maximum of 72 hours. I'm not exactly sure what stage it is in (it claims to have 8 stages in the IFU), and what actual amperage it is putting out at this voltage.

I may try it again this weekend using my bluetooth monitor where I can log the charging process and post it next week. The car I will put it on, has a Battery Minder 2012 AGM on it constantly. I will swap them on Saturday for a couple days to compare the difference again.

It also has a very mild temperature compensation compared to the standard Battery Minder products.

Here is an update of the inexpensive Northern Tools/Battery Minder 1 amp Model #12117TC. I plugged it into a fully charged Interstate H6/Group 48 AGM battery that has been continously connected to a Battery Minder 2012AGM 2 amp battery charger on float.

https://www.northerntool.com/products/batteryminder-plus-battery-charger-trickle-charger-desulfator-12-volt-1-amp-model-12117tc-167981?cm_mmc=Google-pla&utm_source=Google_PLA&utm_medium=Automotive > Batteries & Chargers + Jump Starters > Battery Maintainers&utm_campaign=BatteryMINDer&utm_content=167981&ogmap=SHP|PLA|GOOG|STND|c|SITEWIDE|OOT|AutoAccessories|

Currently it has been connected to the battery for about 17 hours...still in the original charge mode...not sure which of the 8 stages. Charging at a temperature compensated 14.83 showing (temp in my garage was probably mid to upper 30s)...it is presently (late afternoon) showing around 14.74 as temps are probably now in the upper 40s in my garage. Let's see how many hours (or days) it takes to reach float stage.

 

[D1dad]

Here is an update of the inexpensive Northern Tools/Battery Minder 1 amp Model #12117TC. I plugged it into a fully charged Interstate H6/Group 48 AGM battery that has been continously connected to a Battery Minder 2012AGM 2 amp battery charger on float.

https://www.northerntool.com/products/batteryminder-plus-battery-charger-trickle-charger-desulfator-12-volt-1-amp-model-12117tc-167981?cm_mmc=Google-pla&utm_source=Google_PLA&utm_medium=Automotive > Batteries & Chargers + Jump Starters > Battery Maintainers&utm_campaign=BatteryMINDer&utm_content=167981&ogmap=SHP|PLA|GOOG|STND|c|SITEWIDE|OOT|AutoAccessories|

Currently it has been connected to the battery for about 17 hours...still in the original charge mode...not sure which of the 8 stages. Charging at a temperature compensated 14.83 showing (temp in my garage was probably mid to upper 30s)...it is presently (late afternoon) showing around 14.74 as temps are probably now in the upper 40s in my garage. Let's see how many hours (or days) it takes to reach float stage.

View attachment 321473

You’re looking at around 30 hrs. I took readings several times throughout and ended up with similar numbers. It’s like the Seinfeld episode when Kramer tries to run the car that Jerry’s looking at out of gas. Don’t chicken out lol, leave it hooked up. It will eventually float. Every battery I’ve used it on was either fully charged, or not far off. I tell ya that these things are like they’re on a timer.

 

[f355spider]

I tell ya that these things are like they’re on a timer.

So I sent Battery Minder the same question earlier today...is the bulk and/or absorbstion stages on a timer, or based on charge.
I will report what they reply on Monday.

 

[pasadena_commut]

So I sent Battery Minder the same question earlier today...is the bulk and/or absorbstion stages on a timer, or based on charge.
I will report what they reply on Monday.

From the curves:

Bulk charging (constant current) ends at a target voltage which is (slightly) temperature dependent.

Absorption charging (constant voltage, temperature dependent) ends when the current falls below a cutoff value. (Probably also temperature dependent.)

Float charging ends, um, never? Some other types of chargers "test" after a while, to assay the SOC of the battery, and may start a new cycle. The Prologix 2320 curve on the first page shows this. I don't recall that the BatteryMinders ever do that.

I suspect that the BatteryMinder has sanity checks on how long it will wait to end the bulk and absorption stages. That is, it may declare a battery a lost cause if after a week (or whatever) it hasn't hit the the target voltage or current.

 

[f355spider]

I suspect that the BatteryMinder has sanity checks on how long it will wait to end the bulk and absorption stages. That is, it may declare a battery a lost cause if after a week (or whatever) it hasn't hit the the target voltage or current.

The Battery Minder tech told me previously, on this cheapo "wall wart" charger, that it times out at 72 hours. I don't recall if it automatically goes to float or stops all together.

 

[f355spider]

D1dad is correct, it was right around 30 hours and it finally switched to float. I'm going to suggest this is a timer of 30 hours of charging, rather than reaching some sort of programmed set point. This was on an otherwise fully charged AGM battery on a Battery Minder 2012AGM just prior to the swap. Its currently floatng at around 13.60 in my around 40F garage at the time of record 3:30pm. It was initially floating at around 13.70 at 4:30am in the morning, when it was much colder in my garage.

I think this is okayish to connect to a larger battery, but I would be very uncomfortable leaving this charging for 30 hours on a motorcycle or ATV battery. If I did, I would immediately press the "float charge" button that skips the charging phases.

 

[Wheel366]

I want to pick up a 128CEC2 to use when I am utilizing my CTEK made Odyssey 15amp charger. Since I have 2 Odyssey batteries, it would allow me to charge both at the same time while using an Odyssey approved charger. I just can't justify purchase at this time.

 

[f355spider]

I want to pick up a 128CEC2 to use when I am utilizing my CTEK made Odyssey 15amp charger. Since I have 2 Odyssey batteries, it would allow me to charge both at the same time while using an Odyssey approved charger. I just can't justify purchase at this time.

I get mine here...I have bought three from them. Nice discount, free shipping and no tax. I gave the third one to a friend for Christmas to use on one of his Ferraris.

https://www.batterystuff.com/batter...r-and-lithium-charger-maintainer-128cec2.html

If you order any accessories, they charge shipping, so I called them and asked if they can throw them in the same box and they agreed.


For maintenance only, you could get one of these for less (out of stock at the moment but you can call or email them on when they will receive fresh stock)
https://www.batterystuff.com/batter...m-charger-maintainer-desulfator-2012-agm.html Its on their approved list...but recommended for the smaller batteries for actual charging, but fine for maintenance on their larger. It uses an approved algorithm.
I have one, but prefer the 128CEC2 for its versatility. Multiple charging rates, multiple battery type settings.

 

[D1dad]

D1dad is correct, it was right around 30 hours and it finally switched to float. I'm going to suggest this is a timer of 30 hours of charging, rather than reaching some sort of programmed set point. This was on an otherwise fully charged AGM battery on a Battery Minder 2012AGM just prior to the swap. Its currently floatng at around 13.60 in my around 40F garage at the time of record 3:30pm. It was initially floating at around 13.70 at 4:30am in the morning, when it was much colder in my garage.

I think this is okayish to connect to a larger battery, but I would be very uncomfortable leaving this charging for 30 hours on a motorcycle or ATV battery. If I did, I would immediately press the "float charge" button that skips the charging phases. View attachment 321698

Good work! Yeah, that whole 30hr thing is just crazy. I didn’t see anything over 14.5, which shouldn’t harm a battery but, this is not a battery minder like we know. My 2012 agm is floating right now @13.7 in 13 degree weather.

 

[f355spider]

My 2012 agm is floating right now @13.7 in 13 degree weather.

Do you have the temp compensation disconnected? That seems really low...should be close to 15vt floating with temp compensation.

 

[D1dad]

Do you have the temp compensation disconnected? That seems really low...should be close to 15vt floating with temp compensation.

It’s maintaining @13.7. I’m good with that number. While charging with the temp compensation connected, it’s 14.7 give or take. I’ve been loyal to only using the agm charger on my only car with an agm, and it’s taking less and less time to switch to maintenance mode. At 1st, this charger took twice as long to finish the job. With the temp comp unplugged it acts more like the standard 2012 as far as amps. I would maybe consider using the northern tool after a long trip that would drain the battery down far enough to make sense. If it were my only charger, I’d press the maintenance button any other time. I actually used a Pulsetech in my sled and zero turn and then hooked the northern tools up to maintain.

 

[pasadena_commut]

It’s maintaining @13.7. I’m good with that number. While charging with the temp compensation connected, it’s 14.7 give or take. I’ve been loyal to only using the agm charger on my only car with an agm, and it’s taking less and less time to switch to maintenance mode. At 1st, this charger took twice as long to finish the job.

Are you saying that when the battery is discharged it is now taking half as long to run the full charge cycle to the point where it goes to float? That wouldn't be good, that would mean the battery is losing capacity so the same amount of current "charges" it faster.

If the battery has been on a charger or driven recently it is a good idea to turn on the headlights for a while (30s, 60s?) to bleed off the surface charge. Then wait around 5 minutes for it to recover. (This assumes a temperature like 25C, it probably needs much longer if the battery is cold.) Then once the battery voltage bears some relation to the actual SOC attach the charger. For instance, the BatteryTender Jr. will go straight to float on a battery if this isn't done, even if the actual SOC is way below 100%. The Harbor Freight 4A charger (it isn't really) had the same problem. I think that all chargers should do that themselves - if it sees a ~100% SOC voltage pull some current out, let the battery recover, then decide what to do. Many, perhaps most, don't.