During the week I bought this Solar Lighting Kit.

http://www.topraysolar.com/product_details.aspx?pid=8&id=173

Mainly for outside use when we get power cuts.

It actually works pretty well.

Bearing in mind we might not get a power cut for a month or two.

Do I leave it running all the time. Continuos charging?

Switch it off sometime?

Or use the lights every evening regardless of power cuts.

What is the best option to preserve the life of the battery?

Any indication what sort of battery the beast has (nothing on the website)?

If it has mains charging I would fully charge it then leave the panel in the sunshine to keep things topped up.

Thank you young man.

No mains charging. Only cost 1,900 Baht so not expecting too much.

The 6W panel will charge that 12V 7AH (84Wh) battery in about 14 hours of full sun (2 days).

I would leave it in the sun permanently, the panel won't exceed the C/10 charge rate that the battery can withstand permanently

Keep the box in the shade, the battery won't like being hot.

Cheers mate. Great help.

You can only bank on around 5 hours of charging time per day (on a good day), so that means ~30Wh/day of charge, which factoring in some losses means about 27Wh usable capacity, if used daily.

At this, the battery will only be around 36% depleted, which is very good for lifespan... Just make sure you're not using more than 27Wh per day - otherwise the battery will not be fully recharged, and will eventually slip into depth of discharge states that will severely limit is lifespan.

Thanks.

looks perfect then for a couple of LED lights turned on for 3 or 4 hours a night.

Even better when one of the frequent power cuts occur.

We used to use an old car battery set up but having to keep charging the battery was a pain,

I think the 12V/7AH battery is the same as used in many emergency light systems and UPS's.

So when the battery dies out in 1.5 to 2 years, you can buy a new one in Home Pro for about 600 Baht.

There's also a 9AH battery in the same size for a little more dosh, could be the difference between sitting in the dark and being enlightened.

It's the same battery as in a simple UPS, the advantage of the UPS is that it gives you 230 AC that can power more domestic appliances.

You can replace the battery with any 12 battery also larger, like a car battery for example, but than the solar panel would take much longer to charge.

I've replaced the batteries in my UPS with external 100 Ah car batteries that can last trough much longer power cuts. The mains seems to get less dependable in the past year. The ultimate solution is a solar roof with a powerbank, Tesla Powerwall for example if it becomes available in Thailand.

If it's the same battery than used in UPS’, then it don’t like to be completely drained for power, it will die quickly, so in case of power cuts, don’t run the battery dry (too often).

I’ve been using normal computer UPS’ as backup power for some light during a number of years. I removed the small internal batteries and made a wire to larger external ones, that give some 18Ah or about 200 watt (VA), extending the battery powered time span. The larger batteries cost about 1200 to 1600 baht. Lifetime is limited, if used often and/or running completely dry. Did lot of calculations for a solar powered backup system, but that was very far from worth the investment compared to just charging with an UPS – at that time, 6 years ago, the panels are much cheaper now.

I tried to use car battery that is cheaper per Ah (bought a brand new 80Ah for the purpose), but that – for one or other reason - don’t work with my various UPS’.

It's lead acid. Terrible option by my opinion. Drain it to 15% 2 times and it's for garbage.

Check this out:

If it's the same battery than used in UPS’, then it don’t like to be completely drained for power, it will die quickly, so in case of power cuts, don’t run the battery dry (too often).

I’ve been using normal computer UPS’ as backup power for some light during a number of years. I removed the small internal batteries and made a wire to larger external ones, that give some 18Ah or about 200 watt (VA), extending the battery powered time span. The larger batteries cost about 1200 to 1600 baht. Lifetime is limited, if used often and/or running completely dry. Did lot of calculations for a solar powered backup system, but that was very far from worth the investment compared to just charging with an UPS – at that time, 6 years ago, the panels are much cheaper now.

I tried to use car battery that is cheaper per Ah (bought a brand new 80Ah for the purpose), but that – for one or other reason - don’t work with my various UPS’.

I recently pimped 2 different UPS' with 100 Ah car batteries and both work like a charm.

You only have to be careful to stay well below the UPS max load, best is half or below, because the UPS is not built to run full for a very long time and will get hot.

If it's the same battery than used in UPS’, then it don’t like to be completely drained for power, it will die quickly, so in case of power cuts, don’t run the battery dry (too often).

I’ve been using normal computer UPS’ as backup power for some light during a number of years. I removed the small internal batteries and made a wire to larger external ones, that give some 18Ah or about 200 watt (VA), extending the battery powered time span. The larger batteries cost about 1200 to 1600 baht. Lifetime is limited, if used often and/or running completely dry. Did lot of calculations for a solar powered backup system, but that was very far from worth the investment compared to just charging with an UPS – at that time, 6 years ago, the panels are much cheaper now.

I tried to use car battery that is cheaper per Ah (bought a brand new 80Ah for the purpose), but that – for one or other reason - don’t work with my various UPS’.

I recently pimped 2 different UPS' with 100 Ah car batteries and both work like a charm.

You only have to be careful to stay well below the UPS max load, best is half or below, because the UPS is not built to run full for a very long time and will get hot.

Thanks – maybe I shall try again; still has the car battery standing doing nothing-at-all.

The sealed UPS-batteries seems to operate at 13.5V to 15.0V whilst a car battery runs 12V – my UPS’ made problem when connected, just charging and no load on output. The car battery however works fine on a standard 500W inverter with transformer output, 220V, whilst a backup battery produces an output of 240V.

A car battery is cheaper per Ah compared to backup batteries, but a car battery may need some maintenance...

13.5 and 15 volt are the values for trickle charging and charging, they are similar for many 12V batteries.

The car battery is made to bump around for several years in a steaming hot engine compartment, so it will have an easy life in a house. I expect them to last longer than in a car with an occasional refill of water.

Charge the car battery first so you give the UPS charger a chance, my lighting UPS (800VA) happily keeps a car battery topped up but needs a little help to recharge after a long power failure (rare as we have a genset).

A thought, the UPS is a 12V one isn't it? Many have two 12V batteries in series for 24V and thus will need two car batteries.

The car battery is made to bump around for several years in a steaming hot engine compartment, so it will have an easy life in a house. I expect them to last longer than in a car with an occasional refill of water.

Hmmmmmmmmmm.

A car battery is designed for large Amp discharges for a very short amount of time, and then be quickly re-charged. Try 4-5 deep discharges and it will be toast. A car battery has thin hard lead plates (to handle the bumping found in cars)

A deep cycle battery is designed for smaller discharges over a period of time. With a daily discharge of around 20% you should get a good few years depending on quality of battery. This battery will have fewer but thicker and also softer plates.

And for anyone thinking of connecting multiple 12V batteries in parallel to get greater storage, please read and understand this. It will save many headaches.

http://www.smartgauge.co.uk/batt_con.html

I ended up buying another one and now use them every evening whether there is a power cut or not.