Battery Powered LED Longevity

Hi all,
This is my first post and please forgive me as I am not an engineer or electrician or any combination thereof
The outcome I am seeking is very low Lumen from a strip of twenty(ish) LEDs over 1600mm. I want to use a simple off-the shelf battery and I want the illumination to last for as long as possible as changing the battery is 'extremely' difficult due to the location (we are talking scaffold access).
There is a mains supply and there is also space for a transformer (? if that is the right word) to bring the mains over to LED requirements but if I can get a battery to last 5 years there is no need to pursue that route.
Any thoughts would be welcome including 'bite the bullet and use the mains'.
Many thanks in advance,
Joe

Use the mains, you're not going to get any worthwhile light at all (if indeed any) if you're running low enough current for the battery to last 5 years - it would also cost a great deal more to power from batteries.

A high capacity car battery would light a single 5mm Led for 6 months, assuming the battery didnt self discharge and was capable of a deep cycle.
So you'd need one heck of a battery for a uselfull amount of light for that long, plus rechargeable batteries tend to self discharge.
What I just said in a long way was the same as Nige, get someone to put a power cable in.

solar > battery > LED possible?
do you have the led strip already? whats the current consumption?
does it have to operate 24 hours or only at night?

I had a similar problem, with a storage shed away from the house. Making a trench, running the conduit and wire, would have cost me hundreds of dollars. So I just went the solar cell and LED route, using components from cannibalized cheap garden lights.

dr pepper said:

A high capacity car battery would light a single 5mm Led for 6 months, assuming the battery didnt self discharge and was capable of a deep cycle.
So you'd need one heck of a battery for a uselfull amount of light for that long, plus rechargeable batteries tend to self discharge.
What I just said in a long way was the same as Nige, get someone to put a power cable in.

Click to expand...

Nigel Goodwin said:

Use the mains, you're not going to get any worthwhile light at all (if indeed any) if you're running low enough current for the battery to last 5 years - it would also cost a great deal more to power from batteries.

Click to expand...

YEP... I will USe The Mains. Thank you all!

Thank you all. Solar and Battery simply are not viable. Mains it is. I will figure it out from here. Joe