Battery charger: explanation of functions and buying advice

Hello!

I've been feeling a bit anxious lately about my battery dying.
It looks like my charger has failed.

Let's start from the beginning:
I actually have 3 chargers, one of which is a very old, basic one from the former East Germany that only charges at 4 amps, but it still works.
Then a very small, plug-in charger for my motorcycle batteries, which also works and switches off, or goes into trickle charging mode, when the battery is full.

The 3rd. I bought a charger a few years ago from the bargain bin at a supermarket for €19.95. It's a CTEC charger, suitable for batteries from 2 or 5 Ah up to 225 Ah.
It's been acting up for a while now; it's not fully charging the batteries.
That really sucks. That thing probably never worked.
It turns off, switches to battery saving mode, but the batteries are not fully charged.

I've always thought that batteries were either full or broken.
However, that doesn't seem to be the case; with that old East German device, they charge and then also function. Even though charging large batteries can take several days.

Well, I think it's time for something new and proper.

My demands are:
Only 12 volts would be sufficient.
Suitable for batteries ranging from approximately 10 Ah to 200 Ah.
Automatic shut-off when the battery is full. So that I don't have to constantly monitor the charging process.
It should be suitable for all types of battery construction, specifically those related to lead-acid car batteries.
It would be nice to have an analog display for the charging current, but it's not essential.
The charging current should be approximately 8 to 10 amps.
The preservation charging function is not necessarily required.
The jump start function is not a necessity either.

I've done some reading on the subject, so it's likely that the charging process usually starts with a constant current until a certain voltage is reached, and then continues with a constant, safe voltage.

I also took a look at E***, and they have quite a selection.
But I also want to buy something that works and that I can understand.
I've seen devices that don't have any adjustment options, and I wonder how they intend to determine whether it's a motorcycle or a truck battery.

Then there's always the recommendation: For 5-160 Ah, or for 2-90 Ah, this is so important because my largest battery is 200 Ah?

Okay, please write something about the topic. I was thinking of a price range of up to around €100.
Perhaps someone here has experience with the device and can confirm that it works.

Hello Steffen,

If I remember correctly, there was a discussion about different types of chargers some time ago, but I can't seem to find it right now.

I personally use a CTEK MXS10 (maximum charging current of 10A). I can't fault its performance; it works perfectly. Do you have a CTEK or CTEK charger? I once saw something at Aldi that looked quite similar to mine.

Best regards, Rainer.

dieselschrauber wrote:

Hello Steffen, If I remember correctly, there was a discussion about different types of chargers some time ago, but I can't seem to find it right now. I personally use a CTEK MXS10 (maximum charging current of 10A). I can't fault its performance; it works perfectly. Do you have a CTEK or CTEK charger? I once saw something at Aldi that looked quite similar to mine. Best regards, Rainer

Sure, the subtle difference between cheap and good CTEC/CTEK.
I don't know of any CTEK products that cost less than 20€.
I own several different chargers, and the CTEK XS 25, which can charge at 25 amps, has proven to be the best for car batteries. It easily charges everything, from small 12Ah motorcycle batteries to large 200Ah batteries!
Even though charging a moped battery is not recommended with the large 25A CTEK charger, it still works perfectly well.
The "Supply" function is also excellent, as it provides a constant 13.8V up to 25A – which is very useful for checking the electrical system during troubleshooting without having to run the engine. The workshop that smells of exhaust fumes won't be a thing in the winter anymore.
Similarly, in the height of summer, it can be used as a great voltage regulator for my compressor cooler to have ICE-COLD beer.

The device only refuses to charge the battery when it's been discharged to a very low level, below 3 volts. Simple solution: Press the "Supply" function - then a constant 13.8V is applied. 5 minutes is enough, then switch to charging mode - it works .

It wasn't cheap, but I'm still thrilled with it!

Hello everyone!

dieselschrauber wrote:

... I personally use a CTEK MXS10 (maximum charging current of 10A). I can't fault the function; it works perfectly. ...

I completely agree; we use the same device here and are absolutely satisfied with it.
The 10A power supply and the refurbishment functions are particularly interesting here.

Best regards from Munich!

. . . or something similar.

The highlight of these devices, in my opinion, is the lack of unnecessary digital features, but they still offer voltage limiting, which simulates a low-power alternator from the battery's perspective.
A lead-acid battery actually doesn't need much more than that http://www.conrad.de/ce/de/product/841187/Einhell-Werkstattladegeraet-BT-BC-22-E?ref=searchDetail.
(unless you switch it to trickle charge mode, IF the device remains connected for days or weeks and the battery is fully charged).

Hi.

I also have a similar transformer mess that probably fried my old Passat battery (because I left it connected for too long without supervision).

Then there's the Aldi-branded "Auto XS" electric car, which I've been using for my "nighttime charging via the trailer hitch" experiments. I wonder if it's not actually fully charging... Hmm, I need to check that first.


What I'm missing, precisely, is that.

Quote:

Particularly interesting here is the 10A power supply

.

The transformer debris currently allows for one battery replacement as a buffer, but I didn't pay attention to the voltage during the replacement. I turned on the light for steaming.

Next, I want to have a connection point in the trunk so I don't always have to "open" the trailer hitch.
The large CTEK even comes with screw terminals with connectors ).

m;

dieselmartin wrote:

I also have a similar transformer wreckage that probably fried my old Passat battery (because I left it connected for too long without supervision).

Then it turns out that it's not just "any old wreckage," but rather "a different kind of wreckage":
My charger with voltage limiting, your device without voltage limiting - with something like that, after just a few days of continuous operation, you'll damage even a relatively healthy battery through overcharging.
Unless the battery happens to have such a high leakage current that the output voltage of the charger is limited to a maximum of 14.4V.

"My debris" is by Absaar and apparently has no limit.

Even in the "normal" position, it was 15.x volts after 1-2 hours...

m;

Hello everyone!

I found the post that Rainer mentioned on a related topic.
/viewtopic.php?t=27407&highlight=ctek

ulf wrote:

... ...it simulates, from the battery's perspective, an alternator with low power. A lead-acid battery doesn't actually need much more than ...

Until I bought the 10A Ctek charger, I, like an aspiring battery expert, was also convinced that nothing could beat a (temperature-compensated) laboratory power supply with a precise output voltage.
The link above made me think, and further research online led me to Ctek, BECAUSE it charges with "pulse technology" (!!!), which no other charger really does. CTEK also doesn't disclose any information about the programming of the µPC, nor does it reveal when which charging strategy leads to the best results.

A little vomiting game:
The battery in my T5 (Varta, still the original one from the factory!) has been weakening for about 4-5 years, and 2 years ago it was already clear to me that it wouldn't make it through the next winter. The time before was mainly during the winter, and every night when it was extremely cold, the batteries were recharged using a laboratory power supply.
So, I bought a Moll EFB back in the summer, and it's still in the basement today.
Why??
Since I bought this charger out of sheer curiosity, the now 12-year-old battery hasn't weakened, and it's probably connected for about twice over the weekend during the winter months. Certainly not (anymore) on a daily basis.
Here's my experience with charging lead-acid batteries using decent chargers (i.e., NOT cheap junk/imitations!!), and I don't think this is a coincidence .

Until then, I saw it the way Ulf did, but I have now been personally enlightened.

Here's something more about the "transformer debris":
This is state-of-the-art technology from the 1960s .
And even back then, these [devices/items] were only allowed to be connected with the battery disconnected, and of course, the connection time was limited – depending on the battery charge level, as one might guess.
You definitely won't be able to fully charge the battery with something like that, but it will likely damage it and cause it to drain quickly. At the very latest, when the lead sludge from below is swirled into the separators due to the severe overcharging or gas evolution, it will break down shortly thereafter.
Therefore: Anyone who still has "transformer debris," THROW IT AWAY!!!
Even with a laboratory power supply, a sulfated battery cannot be restored. With a (magical *g*) pulse charge, definitely.

My practical tip: The 10A version is (for me!) the optimal balance between ease of use (or lack thereof) and usefulness. With a 5A fuse, you can no longer safely provide a buffer, and with 25A, it becomes much too large and heavy for occasional household use.
But ultimately, each person must decide that for themselves.
Starting with model 10A, Ctek offered an external temperature sensor as an optional accessory for temperature compensation. This sensor could be correctly attached to the battery during charging, although its use was not mandatory.

Otherwise, everything has already been written in the link above (post).

Best regards from Munich!

I have an Einhell transformer box that I use in my garage as a power adapter for a car cooler. The only goal is to have cold beer after work, and Prussians and Bavarians are surprisingly not that far apart on that one. With a minimal load connected to limit the voltage, this thing has allowed me to perform several uninterruptible battery changes. Similarly, to prevent the battery from being drained while the engine is off when operating electrical devices. This device might draw 10 amps, and it can handle short bursts of 15-16 amps thanks to the slow-blow fuse.

For wellness... The Lidl charger draws 0.8 or 3.8 amps, switches to trickle charging, then pulses, and also offers a higher charging cut-off voltage for AGM batteries. I have my own panel connected to it with voltage and current displays, and it appears to have a simple temperature correction. It definitely doesn't damage anything. I occasionally use it for motorcycle and car batteries, but trickle charging isn't really worth it considering their short lifespan and low price. Neither Varta nor Yuang lasted for more than two years. A 900cc secondary battery is too large for the compact size (12-14 Ah).

That Lidl thing used to cost 18 euros.

Hello Spati!

Your previous statement has already been discussed in the link (post) titled "charging/discharging".
Look first, then write .

Best regards from Munich!

Okay, hier ist die Übersetzung:

"Then please delete."

DieselBär30x wrote:

Until I bought the 10A Ctek, I, as someone who fancied himself a battery expert, was also convinced that nothing could beat a (temperature-compensated) laboratory power supply with an exact output voltage. The link above made me think, and further research online led me to Ctek, BECAUSE it charges with "pulse technology" (!!!), which no other charger really does. CTEK also doesn't disclose any information about the programming of the µPC, nor does it reveal when which charging strategy leads to the best results. Bitte gib den Text an, den du übersetzt haben möchtest. Here's something more about the "transformer debris": This is state-of-the-art technology from the 60s

, but it also "pulse-charges" (with un-smoothed half-wave rectification), which is something you've recently started advocating for .

Quote:

With something like that, you definitely won't fully charge the battery, but you will likely overheat and quickly drain it.

However, once the transformer debris has a (correctly adjusted / temperature-compensated) voltage limiter, you can fully charge the battery without overheating it - and with common thyristor technology, also with pulsed charging currents.

I'd be interested to hear your explanation of why the CTEK is still better than a voltage-limiting transformer "thing" (which you might have...). Would you like to get your T5 battery back in shape?

DieselBär30x wrote:

My practical tip: The 10A variant is (for me!) the optimal balance between (ease of) use & functionality. With 5A, it's no longer possible to safely buffer, and with 25A, it becomes much too large and heavy for occasional home use.

I chose the MXS 25 back then, for the following reasons:
- More robust charging cable/clamps, no plug and socket connection.
- Higher charging current.
"If the battery is dead, I don't want to have to wait around for a long time."
- As a power supply, it provides sufficient power, even if a few control units or the radio suddenly turn on.


The only drawback I can find is not the size or weight, but that the device can only be used/should only be used with batteries starting from 40 Ah.
It's probably technically possible that it could damage smaller batteries, but mine, which is 33 Ah, was still charged .

I just bought this professional, high-power device for small batteries from Aldi, and it actually cost 14 euros. While there's a negative sentiment involved, it somehow also seems to be charging the battery.

Hello!

Thank you for the answers and suggestions.

Okay, it's going to be a CTEK MXS 10. With battery temperature sensor.

This is a perfect fit for my needs and my vehicles, and it complements my other chargers.
If everyone is so enthusiastic about it, there must be something to it.

I just need to figure out where I can get it at the best price. The local auto parts wholesaler wants 20% more than what they cost new at E***.

After charging for 3 days with 4 amps, my tractor battery is now fully charged and is working even in the cold, because I needed to use it briefly today.
But the battery is also already 10 years old...

Steffen G wrote:

I just need to check where I can get it at the best price,

119.00 EUR at Amazon?