Batteriehülle: Kosten vs. Nutzen? | Posts 16+

Ulf wrote:

Quote:

Hm... let's say, for example, that the battery is connected to the music system every half second for 0.1 seconds with an average current of 15 amps. In doing so, it loses 1.5 As each time, which is only about 0.0007% of the nominal capacity of a 60Ah battery, and is recharged by the next bass beat. Sure, that results in approximately 3600 charge-discharge cycles for a 30-minute disco session, but it's only "microscopically small" -> are they also that harmful?

What's less important is the amount of power drawn from the battery, but rather the short, high inrush current. For this reason, all consumers in a vehicle are typically designed so that the inrush current is smaller than the possible rate of change of current produced by the alternator (approximately 200A/s). If this happens occasionally, it's statistically undetectable in terms of battery life, but if it happens multiple times per minute or hour, it does reduce the battery's lifespan. That's why more and more large consumers are being equipped with control units that allow for a slow start-up or switch-on (e.g., fan control, seat heating, blower...). This expensive effort isn't undertaken without reason...

Best regards,

heating fossil fuels

Hi,

Temperatures above >20°C are not inherently harmful to the battery. The problem is that as the temperature increases, the charging cutoff voltage decreases significantly. If the battery is warm, it will be constantly overcharged, which can significantly shorten its lifespan.
Cold temperatures have little effect on the battery, primarily due to two key factors: First, the chemical and mechanical processes within the battery are largely unaffected as long as the electrolyte doesn't freeze. Second, the charging cutoff voltage is so high that it is unlikely to be reached by the charger anyway.

Regards,
Sure, here is the translation of the text from German to English:

"Micha"

Mephisto wrote:

Hi, Temperatures above 20°C are not inherently harmful to the battery. The problem is that as the temperature increases, the charging cutoff voltage decreases significantly. If the battery is warm, it will be constantly overcharged, which can significantly shorten its lifespan. Cold temperatures have little effect on the battery, primarily for two reasons: First, chemically and mechanically, it doesn't matter as long as the acid doesn't freeze. Second, the charging cutoff voltage is so high that the charge regulator cannot reach it anyway. Regards, Micha

.

Hello,

However, battery manufacturers have a completely different view on this. For every degree Celsius above the 20-degree mark, there is at least a reduction in lifespan, especially for stationary lead-acid batteries that are very similar to those produced by Bauer. In these systems, the charge controllers are self-evidently temperature-compensated, and the charging curves specified by the manufacturer are always programmed.

Roger wrote:

Mephisto wrote: The problem is that as the temperature increases, the charging voltage significantly decreases. If the battery is warm, it will be constantly overcharged, which considerably shortens its lifespan. . . stationary lead-acid batteries . . . In those cases, the charge controllers are of course temperature compensated, and the manufacturer's specified charging curves are always programmed.

"As far as I know, the car battery chargers are also temperature compensated. Therefore, in my opinion, overcharging can only occur if..."

a) The temperature sensors provide (significantly) incorrect readings: modern lithium battery management systems measure the temperature of the intake air flowing into the engine compartment, which in turn corresponds (approximately) to the temperature of the battery.

b) the charging voltage curve is not suitable for the battery being used.

c) in case of a regulator defect.

Hi,

@Roger: Could you please post a corresponding datasheet? I suspect that the maximum storage time in a discharged state is specified there. But who stores lead-acid batteries in a discharged state? Even at 0°C, after a maximum of one year of storage in a discharged state, the battery would likely be ruined.

Regards,
Sure, here is the translation of the text from German to English:

"Micha"

Mephisto wrote:

Hi, @Roger: Could you please post a corresponding datasheet? I suspect that the maximum storage time in a discharged state is specified there. But who stores lead-acid batteries in a discharged state? Even at 0°C, after a maximum of one year of storage in a discharged state, the battery would likely be ruined. Regards, Micha

.

Hi there,

I can't post datasheets for a specific type, but here is something:
http://www.harmerandsimmons.ru/vorschau/tk/faq/technische_fragen.htm#aw7

Roger wrote:

I can't post datasheets for a specific type, but here is something: http://www.harmerandsimmons.ru/vorschau/tk/faq/technische_fragen.htm#aw7

This is related to the sulfation of the lead plates; the higher the temperature, the more reactive the sulfuric acid becomes.

People's opinions on this vary widely. For example, my batteries always seem to weaken in the winter when the auxiliary heating is running. Again, the lower charge level and potential for deep discharge can lead to faster sulfation.

Hi,

Quote:

I cannot post datasheets for a specific type, but here is this: http://www.harmerandsimmons.ru/vorschau/tk/faq/technische_fragen.htm#aw7

Cough: Quote from the link: "The lower the temperature, the longer the battery life."
It sounds like a simple curve. Why is a family of curves then plotted in the graph below this section?

@Aron:

Quote:

This is related to the sulfation of the lead plates; the higher the temperature, the more reactive the sulfuric acid becomes.

Simply put, that's exactly how it is. And the increasing "reactivity" of sulfuric acid with decreasing charge is also the reason why a lead-acid battery should always be as fully charged as possible if it is to have a long lifespan.

So, with a warm battery, you have two effects:

The optimal charging voltage is higher than that at 20°C, which means that with proper full charging, the acid tends to attack the lead plates less.

2.) Due to the higher temperature at a given charge level, the acid attacks the lead plates more aggressively.

Hats off to everyone who can confidently say, without calculation, which effect will prevail!

@Ulf:

Quote:

As far as I know, the automotive alternator regulators are also temperature compensated.

Really? Even with your Polo and my Golf?

Quote:

b) the charging voltage curve does not match the battery being used

.
What could possibly be wrong? As long as you don't use a lithium-ion battery instead of a lead-acid battery, the temperature coefficient will always be the same.

Regards,
Sure, here is the translation of the text from German to English:

"Micha"

Mephisto wrote:

That sounds like a simple curve. Why is then a family of curves plotted in the graph below this section?

These are the discharge curves of battery types with different nominal service lives (10, 8, 5, and 3 years) according to Eurobat, showing their expected lifespan at various temperatures. While car batteries may have slightly different designs in detail, the fundamental chemistry is the same, and the plate structure is very similar.

In automotive applications, accelerated aging is often accepted as unavoidable because there are no alternatives. In many cases, these components only last for about 3 years, although exceptions always exist.

Mephisto wrote:

With a warm battery, you have two effects: 1.) The optimal charging cut-off voltage is higher than that at 20°C, so that with correct full charge, the acid tends to attack the lead plates less.

This is incorrect: the warmer the battery, the lower the gassing voltage.
With proper temperature compensation of the charging voltage, this is not a problem.

Quote:

Quote: As far as I know, the automotive alternator regulators are also temperature compensated. Really? Even in your Polo and my Golf?

In the Polo: yes.
Golf: Troubleshooting -> Immediately after a cold start, use a hairdryer or heat gun to warm up the regulator and simultaneously monitor the charging voltage using a digital multimeter (DMM). The voltage should decrease while warming and then increase again when the hot air is turned off.

Quote:

Quote: b) the charging voltage curve does not match the battery being used . What might not be right? As long as you don't use a lithium-ion battery instead of a lead-acid battery, the temperature coefficient is always the same.

Not quite: depending on the manufacturer's "fine chemistry" of the cells, the charging voltage curve probably shifts slightly up or down.

ulf wrote:

Not quite: depending on the manufacturer's "fine chemistry" of the cells, the charging voltage curve probably shifts slightly upwards or downwards.

Sure.

Therefore, the battery also needs to be properly coded for newer vehicles.

Sure, here is the translation of the text from German to English:

"Hi,"

Quote:

The warmer the battery, the lower the gas evolution voltage.

Okay.

I would be surprised if the charger in your Polo has temperature compensation. How could one reasonably infer a value from one temperature to another?
You probably shifted the Fermi level in the pn junction of the rectifier diodes using your hairdryer.


Regards,
Sure, here is the translation of the text from German to English:

"Micha"

Mephisto wrote:

I would be surprised if the charging regulator in your Polo ( ) is temperature compensated. How could one reasonably infer from one temperature to another?

"Reasonably" is a question of definition here... but compensating based on the engine compartment temperature (alternator cooling air) is still better than nothing.

Someone had once looked up my regulator number in Bosch documentation and found that my regulator is temperature compensated.

Quote:

You probably shifted the Fermi level in the pn junction of the rectifier diodes with your hairdryer.

Even if that were the case: the result counts.

@ulf

An amplifier can draw significantly more current. I've already measured up to 150A... if you factor in that value, things look quite different, especially since there's also additional current flowing to the car radio and other components.
"The power supply can be quite strained in some cases (for example, the lights might momentarily flicker and go out without a capacitor)."

ulf wrote:

Someone had once looked up my regulator number in Bosch documentation and found that my regulator is temperature compensated.

In practice, this can only be reliably achieved if a temperature sensor is installed, for example, beneath the battery.
On my EDC 15, I have a voltage regulator connected to the alternator. It sometimes outputs 14.2V and other times 14.5V, depending on the air conditions and its mood, but it has nothing to do with the battery temperature.

The vehicles with the EDC16, Siemens 5WS, and SID803 ECUs that I am familiar with use the MSGR protocol and have a sensor directly connected to the battery.

Sure, here is the translation of the text from German to English:

"Hi,"

Quote:

and have a sensor directly connected to the battery

.
That also makes sense! You wouldn't measure the temperature at the North Pole to estimate how warm it is in Europe.

It's possible that something in Ulf's regulator is temperature-compensated. But does it actually involve adjusting the battery charging voltage to account for the temperature-dependent charging cutoff voltage?

Regards,
Sure, here is the translation of the text from German to English:

"Micha"