So you chose a motorized mount or you have other equipment that requires power and does not come with an integrated battery, then you need to figure out how to power your equipment.

Power Plugs

Let’s start by addressing that most astronomy equipment typically uses old-school power plugs. I guess this allows us to plug in the telescope into the cigarette-lighter plug still available in cars today.

When appreciating the night sky from home, power convertors with a cigarette-lighter power plug are available on the market.

Power Banks

They are small, convenient, easy to connect, and easy to recharge, but also expensive. They are good enough when observing and you just want to power a telescope mount with the purpose of using the goto functionality.

But everyone I know, like myself, who started with a battery like this and then decided to get into astrophotography has regretted their purchase. They simply cannot provide enough power for a complete setup, over the longer periods of time that imaging sessions typically take.

Batteries & Battery Chargers

When power requirements are more important, proper deep-cycle batteries are unavoidable.

They do require a lot more maintenance than the power banks though:

• Some need to be on a charger at all times to keep them healthy.
• Some might leak some of the chemicals that they contain if not handled properly, so you need to store them in a properly ventilated room, …
• You also want to keep them away from kids as the power connectors are not well protected.

But they are powerful and a lot cheaper.

Do not pick car batteries though, those are made to provide short bursts of power for a very short amount of time. That does not sound like astronomy, right?

Splitter

Somehow that power needs to be shared with the equipment that needs it: mount, camera, computer, … . As I want to be able to setup my telescope quickly, I created myself a little splitter box that allows me to power my setup, allows me to charge my phone and allows me to keep an eye on the power charge left available in the battery.

Calculating power requirements

So I had my equipment and a power bank that was not up for the job. I started looking for a replacement and that started with understand how much power I needed to be available.

• Add up how much power of all the different components per hour require (mount, camera, guide camera, Rasberry Pi computer, …).
• You multiple that number by the max number of hours you think you need the equipment to run. I estimated I probably would never do an imaging session longer than 6 hours in a row.
• Add a good amount as batteries do not like to run empty. they might not want to recharge properly if you make them run too low

Then find a battery that can provide the power needed for your setup for the amount of time you had in mind.