I do deep space and planetary imaging from remote sites and I want to extend my options for powering my laptop, cameras, telescope and other electronic accessories.  I have looked at the Optima D31T (75 Ah) but before I make a purchase I would appreciate others' comments about their battery experience and recommendations.

 Skycruiser

I have used a number of power schemes over the years. Most recently, I just finished making a powerpack we jokingly call The Nuke.

It uses three 33AH Glass-mat Technology 12V batteries and is built into a wheeled tool box that is about 12x16x20 inches. It has a battery charger and 1500W inverter, a 12V receptacle, a 12V hair dryer for dew removal, and I'm having a custom-fit Telegizmos 365 cover made for it to keep everything water tight overnight.

It runs my SBIG ST-7XME, two laptops, an STV autoguider, and an AP900 mount all night with plenty of juice leftover to run my 12V electric blanket while I sleep in. Uses about 40% of capacity and recharges in about 6 hours.

The downsides are cost (about $600, most of it in the inverter and charger) and weight (just under 70 lbs).

I have no doubt that it could run the mount, a laptop, and a webcam or similar imager all night long on just one of its three batteries.

12V accessories are your friend. If you have a 12V converter for your laptop you'll save at least half on energy consumption.

Planned upgrades:

• Two additional 12V sockets
• Anderson PowerPole cables and connectors to replace the hard-wired setup
• 12V coffeemaker

I use a size 27 deep cycle battery rated at 105 amp hours with a 400 watt inverter and I also always have a spare size 24 at 85 amp hours with me too. I also made a cable with two male cigarette plugs on it so i can plug it into my cigarette lighter plug and charge them when I'm traveling in my truck.

JJ 

 I use the Optima D34M (55aH) with an 800 watt inverter (I have three 12 VDC outlets in addition to the one on the inverter). I can run my laptop, an LXD-75 SN-10 (w/EQ-G mount), a small LCD monitor (DVD player), and my Canon XTi for a night's worth of observing with this setup.

Steven

My system draws about 6 amp. I had an 80 amp hour deep cycle battery that would run the system for 6 or 7 hours before the dc to dc converter for the laptop dropped out from low voltage.  I wanted to be able to image over two consecutive nights camping out at deep sky sites so a bought another 80 amp hour battery.  One battery runs the laptop, the other battery runs everything else.  With this set up both batteries will go about 21 hours before the voltage drops too low, and they both drop out at about the same time.

HI SkyCruiser,

I have a similar set up , I use three 750 A/h 12V deep cycle batteries, One runs my laptop with a 12DC to 110V cigarette lighter inverter, One runs my dew heaters and I have another one for back up, while the Celestron 17A/h power pack runs my CG5 ASGT mount.

This will run my DSI and setup all night long, the backup is mostly for the nights that dew becomes a major problem, I have a Kendricks dew removal system that runs 4 band heaters.

I also use a enclosure to keep my laptop out of the sub zero weather and protect it from dew.

Dennis

We ran a very similar thread on this topic a month or so ago.  I think it's great that most of us seem to feel that 17AH provided by the stock retail "power tanks" just don't quite get it done.  Looking at pictures etc. we usually arrive at similar resolutions to the problem (except for "the Nuke" - I thank he want to power up Minneapolis! - I can't talk too much on that since one of my main pieces of equipment is a coffeemaker!)  My 55AH Optima deep cycle seems to handle all of my loads easily for a weekend's viewing.