300-03866 7.2V 3700mAh Battery Compatible with Alarm Lynx 5100, 5200, 5210, Lynx Touch 7000
Quick take
This 7.2V 3700mAh rechargeable NiMH backup battery is made to replace the battery used in compatible Honeywell Lynx and Lynx Touch alarm kits, including the Lynx Plus panel and GSM module backup use case. Reviewers who installed it report the system returning to normal behavior, like stopping nuisance beeping. The main caveat is that you must match the correct alarm kit model and connector, and real backup performance can only be confirmed during an actual power outage.
Pros and cons
Pros
- Designed as a replacement battery for specific Lynx/Lynx Touch alarm kits, including support for the Lynx Plus panel and GSM module backup power.
- 7.2V, 3700mAh capacity, using 6 NiMH cells (4/3A X 6) with a 3-pin connector.
- Built around replacing part numbers like 300-03864-1/LYNXRCHKIT-SC with 300-03866/LYNXRCHKIT-SHA.
- Multiple installers report straightforward replacement and normal system operation afterward.
Cons
- Charging and long-run backup claims can’t be validated until there is a real power outage, so evidence is indirect.
- Compatibility is model- and part-number-specific, so mismatching an alarm kit can lead to non-function or charging issues.
- Some buyers report receiving a battery that would not charge, which means DOA scenarios are possible.
What buyers think
Buyer feedback is generally consistent around installation and immediate outcomes. Several reviewers describe it as an exact replacement and note that after swapping the battery, the alarm system stopped the nuisance beeping and everything continued working. Others mention it tested fine and charged within a reasonable timeframe after installation. There is also limited but present negative feedback, including reports of a battery that would not charge, so buyer-review evidence suggests that compatibility and receiving a functional unit both matter.
Who this battery is for
This replacement is aimed at homeowners who need a backup battery for compatible Honeywell Lynx and Lynx Touch alarm systems and related components, specifically kits associated with the listed Lynx 5100, 5200, 5210, and Lynx Touch 7000 family, plus the Lyric controller and Lyric keypad LCP500-L configurations named in the compatibility list.
If your alarm panel or related module is indicating a low battery condition, beeping, or you are simply planning preventative maintenance, this is the kind of battery upgrade that can restore expected behavior without changing your alarm hardware.
Key specs that affect real-world fit
- Voltage and capacity: 7.2V, 3700mAh rechargeable battery.
- Chemistry: NiMH (uses 6 NiMH cells).
- Connector: 3-pin connector.
- Intended backup use: Backup power for the Lynx Plus panel and GSM module.
- Replacement part alignment: Replaces specific part numbers including 300-03864-1/LYNXRCHKIT-SC with 300-03866/LYNXRCHKIT-SHA.
- Physical size: 110 x 68.00 x 17.20 mm (important for enclosure fit).
Pros and cons, in plain English
Why it’s a solid choice
Because it is built as a direct replacement with matching voltage, capacity class, cell type (NiMH), and connector type, it’s a practical option for keeping an older Lynx or Lynx Touch system running without upgrading the whole panel. Reviewers who installed it report normal operation afterward, including reduced or eliminated nuisance beeping.
Where buyers should be careful
Battery performance during long power outages depends on multiple factors (battery age and health, charger behavior in your specific panel, and how the system uses the backup circuit). Also, this product is not “universal,” it is compatibility-specific, so you should verify your current battery part number (and your panel/module model) before ordering. Finally, there is at least some negative review evidence indicating possible DOA or non-charging units, so it’s worth planning for the reality that a replacement process may be needed if the battery arrives defective.
Price and availability
This battery is typically listed as a single 1-pack replacement and is shown as in-stock on the product page at the time of writing. For the most current pricing, use the link below.
How to confirm compatibility before buying
- Match the alarm kit model to the compatibility list, including Lynx 5100, 5200, 5210, Lynx Touch 7000, and the named Lynx/ADemco-style kits listed.
- Verify the original battery part number on your current battery, including whether it corresponds to 300-03864-1/LYNXRCHKIT-SC so it can replace with 300-03866/LYNXRCHKIT-SHA.
- Check the connector type (this one is a 3-pin connector) so the leads and housing will match your panel’s battery bay.
- Confirm physical space using the dimensions (110 x 68.00 x 17.20 mm) to avoid fit problems inside the enclosure.
Verdict
The 300-03866 7.2V 3700mAh NiMH backup battery is a good replacement target for owners of compatible Honeywell Lynx and Lynx Touch alarm systems who want to restore backup power without upgrading their panel. If your priority is correct fit, matching part numbers, and a straightforward swap, this is the right category of battery. Just take compatibility seriously and remember that the full “up to 24 hours” style backup performance can only be truly verified during an actual power interruption.
FAQ
Does this battery support backup power for the Lynx Plus panel and GSM module? Yes. It is intended for backup power for the Lynx Plus panel and GSM module.
What chemistry is this battery using? It uses NiMH cells.
How do I confirm this is the correct replacement for my system? Compare your current alarm kit model and current battery part number to the listed compatible models and replacement part number (300-03866/LYNXRCHKIT-SHA, replacing 300-03864-1/LYNXRCHKIT-SC). Also confirm the 3-pin connector and physical dimensions.
What backup runtime can I expect? The product is described as providing backup power up to 24 hours after a power outage, but real results depend on the system and the actual conditions during an outage.
What if the battery won’t charge after installation? Some buyers report non-charging units, which means it’s important to test charging behavior after install and follow the platform’s return or replacement process if needed.
Frequently asked questions
Specifications
| Product Title | 300-03866 7.2V 3700mAh Battery Compatible with Alarm Lynx 5100, 5200, 5210, Lynx Touch 7000, Lyric Controller Lyric Keypad LCP500-L LYNXRCHKIT-SHA LCP500-4B (1 Pack) |
|---|---|
| Category | Electronics > Security & Surveillance > Home Security Systems |
| Brand | GEILIENERGY |
| Manufacturer | GEILIENERGY |
| Model Name | 300 3866 |
| Model Number | 300 3866 |
| Item Weight | 0.25 Kilograms |
| Number of Batteries | 6 A batteries required. (included) |
| Battery Cell Type | NiMH |
| Battery Capacity | 3700 Milliamp Hours |
| Voltage | 7.2 Volts |
| Reusability | Rechargeable |
| Amperage | 3 Amps |
| Unit Count | 1 Count |
| Battery Weight | 330 Grams |
| Antenna Location | TV Remote |
| Battery Cell Composition | NiMH |
| Recommended Uses For Product | TV Remote |
Available variants
Size
- 1 PACK 7.2V 3600mAh Battery
- 1 PACK 7.2V 1100mAh Battery
- 2 PACK 7.2V 3600mAh Battery
- 2 PACK 7.2V 1100mAh Battery
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