AGM 100AH Deep Cycle Battery
100Ah AGM observatory backup battery for DragonLAIR Pro systems with high-draw motors. Provides 18-37 roof cycles at 50% DOD. Sealed, maintenance-free design.
Out of stock - will ship when available
Serious Backup Power for Serious Observatories
The 100Ah AGM Deep Cycle Battery delivers the capacity your DragonLAIR Pro system demands-and the reserve power to keep your entire observatory running through extended outages. When a 35Ah battery isn't enough, this is the upgrade that matches your investment in automation.
Why This Battery?
DragonLAIR Pro systems use 900W or 1200W motors that draw 40-80 amps under load. That kind of current depletes smaller batteries fast. The 100Ah capacity gives you roughly three times the reserve of our 35Ah recommendation-enough for 18-37 roof cycles on a single charge, even with Pro-level motor draw.
But capacity isn't just about roof cycles. We run two of these batteries in parallel at our own personal observatory. During one extended power outage, we imaged for days without utility power-the observatory kept running while the neighborhood stayed dark. That's the kind of backup this battery provides.
We've deployed about a dozen 100Ah batteries across customer installations over the past two years. They handle the job Pro systems demand, and they give hobbyists who want whole-observatory backup the capacity to actually use it.
Key Benefits
Enough Capacity for Pro System Motors
The math is straightforward: Pro motors draw 40-80A for about two minutes per roof cycle. That's 1.3-2.7Ah per operation. With 50Ah of usable capacity (at the recommended 50% depth of discharge), you get 18-37 theoretical cycles before recharging. Compare that to a 35Ah battery under the same load-only 6-13 cycles. For Pro systems, 100Ah is the right starting point.
Whole-Observatory Backup
This isn't just emergency roof closure-it's extended runtime for your entire setup. With enough capacity, your DragonLAIR can keep the observatory operational through multi-hour outages while you decide whether to keep imaging or close up. Our own two-battery parallel setup has powered imaging sessions through days-long outages.
Expandable with Parallel Configuration
Need more capacity? Connect up to four 100Ah batteries in parallel for 200Ah, 300Ah, or 400Ah total. Use batteries of the same brand, type, capacity, and age for best results. A battery balancer extends service life when running multiple batteries in series or parallel.
Sealed, Maintenance-Free Design
AGM (Absorbent Glass Mat) construction means no liquid electrolyte to spill, no fumes to vent, and no maintenance to perform. Install it inside your observatory enclosure without worry. Mount in any orientation except upside down.
Wide Temperature Tolerance
Observatory environments aren't climate-controlled. This battery handles discharge temperatures from -4°F to 140°F-covering everything from summer heat to winter cold in an unheated roll-off roof. Pair it with a smart charger that provides thermal-compensated charging for optimal battery health across seasons.
What's Included
- Renogy 100Ah AGM Deep Cycle Battery (retail package)
- M8 × 1.25 × 20mm terminal bolts (×2)
- Renogy documentation
Technical Specifications
| Specification | Value |
|---|---|
| Voltage | 12V |
| Capacity | 100Ah (10-hour rate to 10.5V) |
| Chemistry | Sealed Lead Acid (SLA) / AGM |
| Cycle Life | 500 cycles @ 50% DOD |
| Self-Discharge Rate | <3% per month @ 77°F |
| Max Discharge Current | 1100A (5 seconds) |
| Max Charging Current | 30A |
| Float Charge Voltage | 13.5V-13.8V |
| Cycle Charge Voltage | 14.4V-14.8V |
| Terminal Type | M8 bolt |
| Dimensions | 13.1" × 6.9" × 8.6" |
| Weight | 63.9 lbs (29 kg) |
| Housing Material | ABS plastic |
| Discharge Temperature | -4°F to 140°F (-20°C to 60°C) |
| Charge Temperature | 32°F to 122°F (0°C to 50°C) |
| Storage Temperature | -4°F to 140°F (-20°C to 60°C) |
| Parallel Capacity | Up to 4 batteries |
| Warranty | 2 years (Renogy manufacturer warranty) |
Integration/Compatibility
The 100Ah AGM Battery works with all Dark Dragons Astronomy products:
- DragonLAIR Pro - Recommended battery for Pro systems with 900W/1200W motors
- DragonLAIR WiFi Controller - Compatible; provides extended backup beyond the 35Ah minimum
- All DDA roll-off roof systems - Sufficient capacity for any roof motor configuration
The setup mirrors our 35Ah configuration, just with more capacity: connect the battery to your DragonLAIR, add a maintenance charger to keep it topped off, and configure your voltage threshold for automatic roof closure. When utility power fails, the DragonLAIR switches to battery power automatically. Set a threshold-say, 11.5V-and the controller closes the roof before the battery runs too low.
For Pro systems or whole-observatory backup, the 100Ah battery provides the headroom that smaller batteries can't.
Installation/Setup Reality Check
This is a straightforward installation-same process as the 35Ah, just a heavier battery.
Time required: About 15 minutes
Tools needed: Basic hand tools (wrench or socket for M8 terminal bolts)
Skill level: Beginner-if you can connect a car battery, you can set this up
Important: Double-check polarity before connecting. The terminals are clearly marked, but take a moment to verify. And don't mount the battery upside down-AGM batteries handle most orientations, but inverted isn't one of them.
Note on weight: At 64 lbs, this battery is nearly three times heavier than the 35Ah. Plan your installation location accordingly, and consider a battery box for protection and easier handling.
What You Need to Provide
- Battery charger - We recommend a 10A or higher charger for DragonLAIR-only setups. Size your charger to exceed your total load if you're powering additional equipment.
- Cables - To connect the battery to your DragonLAIR
- Battery box or enclosure - Recommended for a clean, protected installation (especially given the weight)
Real-World Performance
We've been running 100Ah batteries on customer installations for two years, with about a dozen deployed across various setups. The batteries handle Pro system demands reliably, and customers using them for whole-observatory backup report the extended runtime they expected.
Our own observatory runs two 100Ah batteries in parallel. During one memorable power outage, we kept imaging for days while waiting for utility service to return. The DragonLAIR managed everything automatically-we just kept shooting.
The Renogy 100Ah AGM is backed by a 2-year manufacturer warranty. For warranty claims or support, contact Renogy directly.
The Right Battery for Pro Systems and Extended Backup
If you're running a DragonLAIR Pro with 900W or 1200W motors, the 100Ah battery is where you should start. If you're a hobbyist who wants whole-observatory backup-not just emergency roof closure-this is the capacity that makes that possible.
For standard DragonLAIR systems where the primary job is emergency roof closure, the 35Ah battery handles the job at lower cost and weight. But when you need more-more cycles, more runtime, more peace of mind-the 100Ah delivers.
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