Creating Portable LED Lighting with 12V 7.2Ah Gel Battery, E27 Bulb Fitting, and Battery Protection

Hello.

I plan to make portable lighting based on an LED bulb powered by a gel battery. It would look like this:

- 12V 7.2Ah gel battery;
- battery protection against excessive discharge (up to 10.5V);
- connector, e.g. through / rocker;
- E27 bulb fitting;
- LED bulb 12V 5W or 7W, for example:



- all this connected with a thin wire, e.g. 2x1 mm2.

Now questions.

1. Will it work?
2. I calculated that a 5-watt light bulb with a fully charged battery should shine for about 17 hours. Right?
3. I will have to buy a battery, so a charger for it. And now the question is what. "Eye" caught my eye:



Specification:

Input voltage 100-240V AC 50Hz / 60Hz
Supported batteries 6V / 12V DC automatic detection
gel, lead-acid, AGM, VRLA, VLA, SLA, WET, GEL, Lead-Acid
Supported battery capacity: above 1.2Ah
Efficiency> 75-80%
Charging voltage approx. 14V for 12V batteries,
7V for 6V batteries
Charging current 1A
Working temperature -10..40st. C (power limitation at higher temperatures)
Dimensions 9.5 x 5.8 x 3.3 [cm]
Other length of the AC power cord approx. 0.5 m, total length of connections (with crocodile clips or eyelets) approx. 1.8 m
The set includes the everActive CBC-1 automatic charger,
user manual PL / EN / DE,
connection with crocodile clips, connection with eyelet terminals
Approximate charging time 5 Ah - 7 h
10 Ah - 14 h
50 Ah - 70 h
100 Ah - 140 h

It seems to me that such a charger, due to the charging voltage of approx. 14V, is suitable for charging the battery during buffer operation, but
fails the test in cyclic operation (where the charging voltage should be approx. 15V). I'm wrong? If not, what other inexpensive rectifier could you recommend me?

McGrinn wrote:

I calculated that a 5-watt light bulb with a fully charged battery should glow for about 17 hours. Right?

Yes, but in practice it is much shorter.

McGrinn wrote:

It seems to me that such a charger, due to the charging voltage of approx. 14V, is suitable for charging the battery during buffer operation, but
fails the test in cyclic operation (where the charging voltage should be approx. 15V).

You're right.
There are some inaccuracies in the description of the charger that you have already partially caught.

Intelligent processor charger for popular 6V and 12V batteries used in the automotive and industry. The perfect 'charger' for car, motorcycle, lead-acid, gel and AGM batteries.

EverActive CBC-1 is a digital, fully automatic universal buffer charger / so-called "intelligent rectifier" for all types of 6V and 12V lead-acid batteries (car, etc.), gel / AGM.

NEW DIGITAL TECHNOLOGY means smaller dimensions, greater reliability, greater efficiency, greater efficiency, lower electricity consumption.

The charger supports most of the car, gel and AGM batteries with capacities above 1.2 Ah available on the market. Despite the relatively low 1A charging current, the charger allows you to recharge and maintain a full charge, even with most car batteries.

Selected parameters:

supported batteries: 6V / 12V DC
automatic detection: gel, lead-acid, AGM, VRLA, VLA, SLA, WET, GEL, Lead-Acid
supported battery capacity: above 1.2Ah
efficiency> 75-80%
charging voltage
approx. 14V for 12V batteries,
7V for 6V batteries
charging current 1A
input voltage 230Vac
dimensions 9.5x5.8x3.3cm
length of the AC power cord approx. 0.5 m,
total length of connections (with crocodile clips or eyelets) approx. 1.8 m
Included:
everActive CBC-1 automatic charger,
user manual PL / EN / DE,
connection with crocodile clips,
connection with ring terminals
approximate charging time:
5 Ah - 7 h
10 Ah - 14 h
50 Ah - 70 h
100 Ah - 140 h
operating temperature -10 to 40 ° C (power limitation at higher temperatures)

Much, i.e. how much? 10 h withstand And where does it come from?
Due to the fact that I know very little about electricity / electronics, I can not capture much from this description. Is it about efficiency?

With a current of 0.4 A, it probably won't be longer.

Below is a more, in my opinion, correct description:

CBC-1 is a unique, miniature design for charging and maintaining 6V / 12V batteries with almost any capacity. The device is completely maintenance-free, automatically detects the type (voltage) of the battery and safely charges. Charging is monitored and automatically terminated (to prevent overcharging of the battery) and resumed at a predetermined decrease in battery charge. The charger can be used for buffer charging of 12V batteries - it keeps the battery ready for any period of time. Resistant to AC power failures.

The charger enters buffer mode when fully charged, with a constant current of 1 A.

This approx. 14V for 12V batteries is a bit confusing.

So there is a dependence that the higher the discharge current, the battery capacity decreases? Could you write something more about it / provide a link to an article? I am curious about it and I don't know how to bite it.

Ah, that was it ... Thanks a lot. Or maybe you know a charger that is good for cyclical use?

McGrinn wrote:

So there is a dependence that the higher the discharge current, the faster the battery will discharge?

And you are right again.

McGrinn wrote:

Could you write something more about it / provide a link to an article?

There is a lot of it on Elektroda.

McGrinn wrote:

Or maybe you know a charger that is good for cyclical use?

According to the description, this is suitable, and a good price.
Maybe Friends other proven models will recommend, because I have been using my own design for years.

I entered the specification of the battery I want to buy and found such a parameter as the C20. This means that the stated battery capacity of 7.2 Ah is measured with a 20 hour duty cycle. As it follows, the maximum current that I can load the battery so that it retains its maximum capacity is 0.36 A. The specification also gives the capacity for a 10-hour cycle and it is 6.85 Ah, i.e. to discharge such a battery within 10 hours I would have to charge it with a current of approx. 0.7 A. I will load it with a maximum of approx. 0.6 A, so theoretically it should easily withstand 10 hours (I assume that it will work at the optimal temperature of 20 ° C and I ignore the drops capacity due to temperature change). I think I made a mistake somewhere?

McGrinn wrote:

I think I made a mistake somewhere?

Perfect - I gave you a "helpful post".

McGrinn wrote:

The specification also includes a capacity for a 10-hour duty cycle and it amounts to 6.85 Ah, i.e. to discharge such a battery within 10 hours, I would have to charge it with a current of approx. 0.7 A

In my opinion, it will not last that long with 0.7 A, but practice will show it.
Can you paste this specification?

Here you are:
http://mwpower.pl/pl/p/file/83b6e5fde773ce2eeaaf1d4ce84dfecd/MW_7%2C2-12MW_7%2C2-12L.pdf " target="_blank" rel="nofollow noopener ugc" class="postlink inline" title="" > http://mwpower.pl/pl/p/file/83b6e5fde773ce2eeaaf1d4ce84dfecd/MW_7%2C2-12MW_7%2C2-12L.pdf

I have one more question. What happens when the battery voltage drops below 12V? The bulb will continue to glow, but it will be weaker or will it turn off?

The bulb will glow, but the battery voltage must not be allowed to drop below 10.5V, stated in the description as cut-off voltage.
This applies to all batteries of this type.

I know about the minimum voltage that can not be exceeded, so I wrote in the first post about securing.

I found an inexpensive charger that charges with 14.4 volts - it should probably be enough. They are "better" and perhaps more suitable chargers (e.g. everActive CBC-4), but much more expensive, so it is not worth buying them.

McGrinn wrote:

- E27 bulb fitting;
- LED bulb 12V 5W or 7W, for example:

Nice - only that LED 12V are not produced in the version with the E27 socket.

And the photos I pasted? In the description, the bulbs are 12V.

McGrinn wrote:

And the photos I pasted?

You will power photos or LED.
In E27 fittings they are produced exclusively for 230V.

Freddy wrote:

McGrinn wrote:

And the photos I pasted?

You will power photos or LED.
In E27 fittings they are produced exclusively for 230V.

I was surprised myself when I saw "twelve" with E27 and E14 threads. Apparently the descriptions of the auctions are wrong:

http://allegro.pl/listing?string=%C5%BCar%C3%...match=base-relevance-floki-5-nga-hou-1-5-0203 " target="_blank" rel="nofollow noopener ugc" class="postlink inline" title="" > http://allegro.pl/listing?string=%C5%BCar%C3%...match=base-relevance-floki-5-nga-hou-1-5-0203
http://allegro.pl/listing?string=%C5%BCar%C3%...match=base-relevance-floki-5-nga-hou-1-5-0203 " target="_blank" rel="nofollow noopener ugc" class="postlink inline" title="" > http://allegro.pl/listing?string=%C5%BCar%C3%...match=base-relevance-floki-5-nga-hou-1-5-0203

In general, the bulb cap does not matter to me, it can be, for example, G4 (E27 and E14 holders seem to be simply more practical to me).

E14 and E27 are Edison thread symbols mostly for incandescent lamps. E14 and E27 are common threads for a 230VAC incandescent bulb mainly used in domestic and commercial applications.

Freddy wrote:

In E27 fittings they are produced exclusively for 230V.

Of course there are LEDs 12V, E27.
There are also traditional low voltage 24V, E27.

Adamcyn wrote:

Freddy wrote:

In E27 fittings they are produced exclusively for 230V.

Of course there are LEDs 12V, E27.
There are also traditional low voltage 24V, E27.

So how is it in the end? Are these auctions correct?

McGrinn wrote:

So how is it in the end? Are these auctions correct?

Of course.

I would like to add here a problem that I encountered when building such a solution - namely, the device that protects the battery against discharge also consumes current, and not a small one at that. Mine, although without a display and LED, consumes approximately 40 mA, which will effectively discharge, for example, a gel battery from a UPS in a short time - unless there are any solutions without consuming electricity?

starfire wrote:

I would like to add here a problem that I encountered when building such a solution - namely, the device that protects the battery against discharge also consumes current, and not a small one at that - mine, even without a display and LED, consumes about 40mA, which effectively discharges in a short time, e.g. a gel battery from a UPS - unless there are some solutions without using electricity?

There are no electronic systems that do not consume current, but 40mA is a lot, the system probably contains a relay that turns off only after the voltage drops. When designing such a device, it is easy to go down to 1mA, and with better elements you can reach uA and you can reduce it until it no longer makes sense, because the current will be so small that it will not affect the battery's operating time, because it will be smaller than self-discharge. Doing it well is not a problem, what you can buy is a separate issue, because the manufacturer always has priority to buy cheap elements, so you have to find out how to make it good.

Of course, even power-hungry protection will not discharge if it is behind the switch.

jarek_lnx wrote:

There are no electronic systems that do not consume current, but 40mA is a lot, the system probably contains a relay that turns off only after the voltage drops. When designing such a device, it is easy to go down to 1mA, and with better elements you can reach uA and you can reduce it until it no longer makes sense, because the current will be so small that it will not affect the battery's operating time, because it will be smaller than self-discharge. Doing it well is not a problem, what you can buy is a separate issue, because the manufacturer always has priority to buy cheap elements, so you have to find out how to make it good.

Of course, even power-hungry protection will not discharge if it is behind the switch.

Thanks for the help, I didn't think of that and the solution was very simple. But it's also nice to know that there is an option to buy/create a module that consumes less power.

If the battery will power the LED bulb, there is no need to install discharge protection, diodes below 9V no longer light up.

klamocik wrote:

If the battery will power the LED bulb, there is no need to install discharge protection, diodes below 9V no longer light up.

Unfortunately, my gel battery was damaged - I use COB LEDs and it seems to me that discharging the battery below 10.5V is fatal to the battery. (it got a short circuit)

Look for a system with a transistor, not a relay. And one that will cut off the current consumption at 11V or a little higher to have time to charge.