35Ah AGM Battery
35Ah AGM observatory backup battery powers your DragonLAIR during outages. Tested for 10+ roof cycles on a 12ft roof. Sealed, maintenance-free, UL certified.
Out of stock - will ship when available
When the Power Goes Out, Your Equipment Stays Protected
The 35Ah AGM Battery is the foundation of your DragonLAIR backup power system. When utility power fails, this battery keeps your controller running long enough to close the roof and protect your telescope, camera, and mount from the elements-automatically, without intervention.
Why This Battery?
This is the minimum capacity we recommend for reliable DragonLAIR backup power-and for good reason. We've tested this exact battery on a 12-foot roll-off roof: a full charge powered 10 complete open/close cycles before the battery needed recharging. That's enough reserve to handle an outage, close the roof, and still have capacity to spare.
We use the MightyMax ML35-12 on dozens of our own installations. It's the right balance of capacity, size, and cost for standard DragonLAIR setups where the primary job is emergency roof closure. If you need more capacity-for a Pro system, longer outages, or powering additional equipment-step up to the 100Ah battery instead. But for most hobbyist observatories, 35Ah handles the job.
Key Benefits
Enough Power When It Matters
A fully charged 35Ah battery provides enough capacity for multiple roof operations during an outage. In our testing, that meant 10 open/close cycles on a 12-foot roof-far more than you'd need for a typical power failure. Your DragonLAIR monitors battery voltage and can automatically close the roof before the battery runs low, so even extended outages are handled safely.
Sealed, Maintenance-Free Design
AGM (Absorbent Glass Mat) construction means no liquid electrolyte, no maintenance, and no spills. You can safely install this battery inside your observatory enclosure without worrying about fumes or leaks. Mount it in any orientation except upside down.
Wide Temperature Tolerance
Observatory environments aren't climate-controlled. This battery handles the temperature swings-hot summer days to cold winter nights-that come with an unheated roll-off roof setup. Pair it with a smart charger like the NOCO Genius 5 for thermal-compensated charging that adjusts to ambient conditions.
Right-Sized for the Job
At 35Ah, this is the smallest battery we recommend for DragonLAIR backup power. It's not undersized, and it's not overkill. You get reliable protection without paying for capacity you don't need-or trying to fit a larger battery into a tight equipment cabinet.
What's Included
- MightyMax ML35-12 AGM Battery
- Terminal screws
Technical Specifications
| Specification | Value |
|---|---|
| Voltage | 12V |
| Capacity | 35Ah (20-hour rate) |
| Chemistry | Sealed Lead Acid (SLA) / AGM |
| Terminal Type | Nut & Bolt (NB) |
| Dimensions | 7.76" × 5.12" × 7.01" |
| Weight | 23.15 lbs (10.5 kg) |
| Construction | Valve-regulated, calcium-alloy grid |
| Mounting | Any position (except inverted) |
| Certification | UL Listed |
| Warranty | 1 year (manufacturer) |
Integration/Compatibility
The 35Ah AGM Battery works with all Dark Dragons Astronomy products:
- DragonLAIR WiFi Controller - Primary use case for backup power
- DragonLAIR Pro - Compatible, though we recommend the 100Ah for Pro systems
- All DDA roll-off roof systems - Sufficient capacity for standard roof motor loads
The setup is straightforward: connect the battery to your DragonLAIR, add a maintenance charger (like the NOCO Genius 5) to keep it topped off, and your backup power system is ready. When utility power fails, the DragonLAIR automatically switches to battery power. You can configure a voltage threshold-say, 11.5V-where the controller will close the roof before the battery runs too low.
Installation/Setup Reality Check
This is a beginner-level installation. If you can connect a car battery, you can set this up.
Time required: About 15 minutes
Tools needed: Basic hand tools (wrench or socket for terminal bolts)
Skill level: Beginner
Important: Double-check polarity before connecting. The terminals are clearly marked, but it's worth taking an extra moment to verify. And don't mount the battery upside down-AGM batteries can be installed in most orientations, but inverted isn't one of them.
What You Need to Provide
- Battery charger - We recommend the NOCO Genius 5 to keep the battery charged and ready
- Cables - To connect the battery to your DragonLAIR (6ft cable available upon request)
- Battery box or enclosure - Recommended for a clean, protected installation
Real-World Performance
We use this battery on dozens of installations, and it's proven reliable in the field. The 10 open/close cycles we measured on a 12-foot roof represents real-world testing, not manufacturer claims-that's what you can actually expect from a fully charged battery under load.
The MightyMax ML35-12 is backed by a 1-year manufacturer warranty. For warranty claims or support, contact MightyMax Battery directly.
Protect Your Equipment-Even When You're Not There
A power outage at 2 AM shouldn't mean waking up to a soaked telescope. The 35Ah AGM Battery gives your DragonLAIR the backup power it needs to close the roof automatically and keep your equipment safe.
Pair it with a NOCO Genius 5 charger for a complete backup power system that's truly "set and forget." Your battery stays charged, your DragonLAIR stays ready, and your equipment stays protected.
Need more capacity? If you're running a DragonLAIR Pro system, want extended backup for longer outages, or plan to power additional 12V equipment from the same battery, consider the 100Ah AGM Battery instead.
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