[Solved] Battery charging, when to disconnect the charger?

Hello.
I know it's not a car forum, but you can probably advise me; I charged the battery (77Ah) with a charger for about 10 hours.
The hand went down to 0.5A. should I disconnect the battery or wait until it drops to 0? Below, the photo of the rectifier with the indication still at 1, now it is 0.5. Greetings.

Check the voltage that the battery already has. if it is over 13.8V, disconnect it already.

The battery should be charged 1/10 the value of the battery, which in this case is about 7.7A --- 8amps, 10 hours is enough, but it is also best to check the charge status of each cell with a pear and this gives a visual overview of the state of the charged battery, whether it will hold potential and its state, the electrolyte density in individual cells is 1.27-1.28 g / m3, besides, there is green, yellow and red graduation on the measuring cup. This method is the best. I personally check it like this and I know how long this battery is enough for me and in what condition it is.

"Safe" in the name of the rectifier should be understood that there is no risk of so-called "overcharge", i.e. exceeding the permissible charging voltage. I consider this to be about 15V - above it may start gassing the electrolyte, which leads to its loss. Nevertheless, it is worth having a meter (a voltmeter, i.e. a cheap universal meter or the aforementioned electrolyte density indicator) - it is not worth taking the manufacturers' word for it.
Such a small current as in the question indicates that further charging does not make sense.
12pavel - 13.8V this is the minimum value of the "on-board" voltage in a running car - mostly the alternator maintains 14-14.4V.

slaveus - there are spelling rules on the forum - point 15 of the regulations.

Oh yeah, and I got it for the spelling I am ashamed the more that I am a Polish teacher Even in the electrode forum, I can't forget about it Thanks for the information. greetings

The most important thing when charging the batteries is the temperature (it should not exceed 50 degrees Celsius). Charging with a small current is the so-called equalizing charge and it can be carried out for several hours, current of 0.05 capacitance. Then all cells are fully charged (it is impossible to build identical ones). water should be checked and topped up (even the so-called maintenance-free), at least once a year.

Gienek, but how can I add water if I don't have access to cells in this battery? (Centra Futura 77Ah) I must admit that I was also wondering how it is in the so-called maintenance-free with water refilling, because after charging something evaporates there. Well, but I have no way of physically adding it there ...

I have a situation similar to my colleague Slaveus.
I was charging 44Ah 2A and the needle dropped to 0.25 / 0.5A. I have 14.5V on the battery with the charger on. When disconnected, it drops to 12.5. I tried to charge it for some time with about 2A (it was a bit bubbling), but after disconnecting it still gives about 12.5V.

I will add that the battery was used for 2 months (straight from the store) and then lay unused for a few months. I thought it was sulfated, but I don't see any raids (although I don't know anything about electricity and I get all my knowledge from the Internet).
Can something be done to make the battery have more capacity after charging?
Thanks for your help, best regards

ssak2001 wrote:

.... I will add that the battery was used for 2 months (straight from the store) and then lay unused for a few months. I thought it was sulfated, but I don't see any raids (although I don't know anything about electricity and I get all my knowledge from the Internet).
Can something be done to make the battery have more capacity after charging?
Thanks for your help, best regards

A few months or how many? .... a charged and unused battery for three months should not become sulphated.
You do not write for how long you charged this battery with 2A.
Read more about how to charge and when there are signs of charging the battery ... e.g. here:
http://www.jak-to-zrobic.pl/index.php/a/3/b/15/c/18/d/0/id/51

slaveus wrote:

Gienek, but how can I add water if I don't have access to cells in this battery?

Centra Futura is a gel battery, 100% maintenance-free and there is no need to refill water. You just have to be careful not to overload it and you'll be fine.

Ziemniak wrote:

slaveus wrote:

Gienek, but how can I add water if I don't have access to cells in this battery?

Centra Futura is a gel battery, 100% maintenance-free and there is no need to refill water. You just have to be careful not to overload it and you'll be fine.

As a colleague above wrote, futura is not a gel battery, and not 100% maintenance-free. If there is no water in it, it should be topped up and it is possible to do so.

I do not know if futura centers are a gel battery, but a car battery is 99% not. Types of lead batteries; acid (classic), VRLA (the so-called maintenance-free with valves where oxygen and hydrogen is to be reduced to water), gel (electrolyte in the form of gel), AGM very similar to gels, but the electrolyte in the glass fiber mats (such a paper placed between the electrodes). I added water to all types. Currently, for example, I use 1320 YUASA EN z1996r series for wna (I filled the water with a syringe). I don't know for what, but the plus cell always lacks the most water.

A few remarks on the topics discussed.
This Centra Futura battery should be advertised. I bought one too, and for the first time in my life I had to. This makes me suspect that the series is the most expensive, but not the best.
The decrease in the charging current of the battery is an indicator of its voltage increase, i.e. it is an indicator of the battery charge. But it is not an indicator of its technical condition. This can only be investigated by observing the voltage across the battery under load. Used battery is quickly charged / charging current drops / but has a small capacity.

Majster wrote:

This Centra Futura battery should be advertised. I bought one too, and for the first time in my life I had to.

And what did they accept the guarantee? I have heard that the recognition of the battery warranty is almost a miracle.

Hello, I will connect to the topic.
I have a Centra 45 Ah battery, serviceable. I have it for 2 years now.
Some time ago I decided to charge it up. I was loading nap. 14.2-14.4 v measured at the output charger before connecting to the battery.
The problem is that the charging current does not drop below 4.5-5 A despite that
I charged it twice for about 11 hours with a break for the night.
In my opinion, it probably has a short circuit inside. The battery has no problem with starting.
But in frost (around -28 C) I took him to the basement because I wasn't sure how he would behave in the morning.
Am I right with this short circuit, because I can't recharge it.
Has anyone had such a case too?
greetings

_iwo wrote:

I was loading nap. 14.2-14.4 v measured at the output charger before connecting to the battery.

Depends on what voltage is 14.4V? If only after straightening through the bridge it is too high to charge the battery about 20V.

Quote:

The problem is that the charging current does not drop below 4.5-5 A despite the fact that I charged it twice for about 11 hours with a break for the night.
In my opinion, it probably has a short circuit inside. The battery has no problem with starting.

So what's your initial charging current for this battery?
If you suspect a short circuit, it is best to measure the electrolyte density for each cell. A cell that has a short circuit will have a much lower density.

Hello, the initial charging current is approx. 8 A but it quickly drops to approx. 5 A and it stays that way.
Probably a good idea to measure the density of the electrolyte.
Oh, please answer the question: the value of 14.4 V (i.e. the maximum charging voltage) is the average voltage measured on the rectifier without load or voltage. measured on the connected battery. because then it is the max value. (peak)?
If I am wrong, please correct me.

_iwo wrote:

Hello, the initial charging current is approx. 8 A but it quickly drops to approx. 5 A and it stays that way.
Probably a good idea to measure the density of the electrolyte.
Oh, please answer the question: the value of 14.4 V (i.e. the maximum charging voltage) is the average voltage measured on the rectifier without load or voltage. measured on the connected battery. because then it is the max value. (peak)?
If I am wrong, please correct me.

14.4 is the peak voltage, i.e. measured on the battery.

12pavel thanks for reply
So the rectifier output is theoretically enough about 10.2V of average voltage?
And transformer to build a rectifier does not have to have 15 or even 18V, only 12V is enough, is it correct?

Practically the 12V transformer will calmly charge the battery. Many rectifiers use higher voltages to speed up charging (charging with higher current).
When using transformers with higher voltages, electronic systems are often used that turn off the charging after the battery reaches 14.4V.

Motronic wrote:

I'm afraid it won't charge.

Will charge. I personally have a transformer with taps (later a bridge) and it charges the battery with 11.2V effective voltage and if not careful, it boils (the battery has over 15V)

Colleagues, you are getting faster. firstly, do not write to the boy about unrecognized complaints, because it may not apply to him, secondly, do not write more about what, how and how much, since it was already explained at the beginning. Don't make your hydro brain !. Undoubtedly, you write interesting things, but that's not the point. Summing up, a colleague will connect and enjoy one of the best BATRIA on our market.

I have a 12V rectifier, which, disconnected from the battery, gives a voltage from 7 to 12V (of course, depending on the setting of the potentiometer). 7V will also charge. Checked. I was surprised too. From this conclusion that the charging voltage is of secondary importance.

czapelka wrote:

From this conclusion that the charging voltage is of secondary importance.

Tension is not secondary, but primary. The voltage will depend on the current the battery will be charged with.

Colleagues ... if we know Ohm's law, we know what dependencies are responsible for charging the battery. Nothing more nothing less.
Greetings.

czapelka wrote:

I have a 12V rectifier, which, disconnected from the battery, gives a voltage from 7 to 12V (of course, depending on the setting of the potentiometer). 7V will also charge. Checked. I was surprised too. From this conclusion that the charging voltage is of secondary importance.

Hardly any rectifier provides a direct voltage, and only such voltage can be measured with a direct current voltmeter - if it is variable (not alternating), the meter will usually show the average voltage, which does not say anything, 10 times more important in the rectifier is the peak voltage. The conclusion is too hasty :)

telwisalfa wrote:

Colleagues ... if we know Ohm's law, we know what dependencies are responsible for charging the battery. Nothing more nothing less.
Greetings.

The battery does not fall under Ohm's law because it is not a resistor. Unless it is about an increase in current with an increase in voltage on the internal resistance, then I agree.

As for maintenance-free batteries, here's a brief overview of:
http://www.akumulator.pl/aktualnosci/artykuly/akumulator-nie-calkowicie-bezobslugowy.html
Most of the maintenance-free ones are so tight that you do not need to add anything, but the construction allows for safe unsealing in the event of pressure increase. These can be, for example, tight, pressed plugs, which will pop out if necessary, and you can add something there.
In my opinion, it is an advantage that there are plugs, and it does not mean that the battery is not maintenance-free, but if it is possible to "service" and who does it bother?

Just for the sake of clarification, the best battery of those with the same starting current is the heaviest one. There is not much lead, there is no long use - the truth is as old as the world. One more remark, Centra is not a product of Polish capital, it is foreign capital. Polish films include Jenox, AutoPart. ZAP Sznajder - all of them at a high quality level, Polish capital and high quality. And do not write nonsense about Centra that it is a Polish company, because it has been sold a long time ago.