# LED Lights and Timer all Battery Powered - HELP

#### JGray2112

##### New Member
good morning, first post...

I have a small project that i'm trying to accomplish and i'm am not very good at electronics, so I've come to all of you. Here's my goal;
I"m trying to power (2) rolls of LED strip lights for 3 hours a day, solely by battery. The project will run in a display outdoors for 100 days. I can change the batteries if needed periodically. Below is a link to the lights. I have no problem wiring, soldering, making battery packs, anything. I just am unsure of how to accomplish all this with a timer (9pm to midnight) and have it all only run on battery. Any help and/or suggestion from anyone would be greatly appreciated.

Lights: https://www.amazon.com/Battery-Operated-LED-Strip-Lights/dp/B07CW6R1CY

Thanks Everyone,
John Gray

#### audioguru

##### Well-Known Member
Amazon and their seller know nothing about the LED light strip.
On one page they say it comes with a battery holder for four AA cells but on the other page it says the LED strip is powered from 5V USB.
They do not say what type of battery produces 5V. An alkaline battery will be 6V, not 5V and might cause the LEDs to burn out or not last long. Maybe the battery should be 5V Ni-MH rechargeable and maybe the USB and battery holder will charge them????? Who knows?

The spec's say the LED strip uses 2.5W. Therefore the current at 5V is 2.5W/5V= 0.5A. The datasheet for an Energizer AA alkaline battery says it will last for about 2 hours but the light will be dimming all the time and might be too dim to see before the 2 hours is finished.
If you use AA size rechargeable Ni-MH cells then each charge will last for about 1.5 hours with not much dimming and you do not know if the battery holder has a charging circuit in it.

Maybe you can buy two 5V/0.5A timers on ebay.

#### AnalogKid

##### Well-Known Member
The LEDs will run on anything from 5 V to 6 V with no problems. The problem is the batteries. If there is no AC power available and you don't want to go with a solar panel battery charging system, then you're gonna pay a lot for batteries.

Another approach is to go with a 12 V battery and a high-efficiency buck regulator. Even with the power loss in the regulator, this will let you get a lot more of the energy in the battery out in a useful manner (no brightness fall-off). 2 rolls = 5 W, times 3 hrs / day = 15 Wh per day. With a nominal 12 V battery, you need 1.25 AH (amp-hour) battery capacity per day between charges. If you have two batteries and rotate them once per week, you need a 12 V, 9 Ah batteries. Stop in to Batteries+ to get a feel for the size and weight of these things.

Questions:

Rechargeable or not?

How many days on one set of batteries?

Anything else we should know?

ak

#### JGray2112

##### New Member
So if i go with a 12v battery how do i get a timer in the mix with the lights?

Questions:

Rechargeable or not? i can do rechargeable but i'd have to remove them, bring them into the office and re-charge them. Unless there was a way to hide a small solar panel. Either way it's not to difficult.

How many days on one set of batteries? The display will be outside for 100 days. It's outside the front door of my workplace. Easy to access and change batteries if needed.

Anything else we should know? Just that i appreciate all the help.

#### AnalogKid

##### Well-Known Member
It's outside the front door of my workplace.
No way to snake a small low-voltage wire out there? A $5 wall wart and a couple of 10' USB extension cables and you're on the air. Add a$10 lamp timer at Wal-Mart and you're done.

ak

#### JGray2112

##### New Member
unfortunately no, i wish we had the ability to get any type of electric on site. This is the thing that is making this most difficult. I've attached what this actually looks like and added yellow likes where i wanted to add the lighting. All the controls/batteries would be held beneath the floor in a 3" cavity. Many this will help some.

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