Description
>> MORE POWER IN THE SAME POCKET. <<
Some builds can’t take a thin pack. They need runtime, and they’ve got the depth to spare. Screens, radios, and microcontrollers that never sleep chew through small cells fast, and the last thing you want mid-session is a brownout.
The Rabbit-Labs 1100mAh LiPo Battery is a custom-built 3.7V, 1100mAh, 4.07Wh single-cell lithium polymer pack in the 102540 form factor: a compact, thick block of energy about the size of a matchbox. Pre-wired leads end in a 2-pin JST connector [CONFIRM pitch], ready to plug into ESP32 boards, handhelds, and custom builds.
Protected, not naked. An onboard protection circuit guards against overcharge, over-discharge, and short circuit, cutting the cell off before a bad day becomes a worse one.
Built for builders. Dense capacity in a small footprint for projects that have the depth but not the length or width for a bigger pack.
Key Specs:
- Chemistry: Lithium polymer (Li-ion), single cell
- Nominal Voltage: 3.7V
- Max Charge Voltage: 4.2V (CC/CV)
- Capacity: 1100mAh
- Energy: 4.07Wh
- Cell Size: 102540
- Protection: Overcharge, over-discharge, short circuit
- Connector: 2-pin 1.25mm JST, red (+) / black (-)
- Dimensions: approx. 10 x 25 x 40 mm (0.39 x 0.98 x 1.57 in)
- Weight: approx. 21g (0.7 oz)
- Transport Testing: UN38.3 tested, ships at approx. 30% charge
Applications that matter:
ESP32 Field Builds. Most ESP32 dev boards have a JST battery port and an onboard LiPo charger. Plug in, charge over USB, and take your scanner, logger, or sensor node anywhere.
Handhelds & Compact Rigs. A dense power source for handheld builds where depth is available but footprint is tight.
Badges & Wearables. Enough capacity to keep LEDs, a display, and a radio running through a long con day.
Replacement & Rebuild. Swap a tired 102540 pack in an existing device. Check polarity first. Always.
1100mAh. Small block. Long night.
▌README.TXT – INSTRUCTIONS FOR USE
Compatibility: A 3.7V single-cell LiPo pack for devices designed to run from one lithium cell and charge it at 4.2V, with a matching 2-pin JST battery port. It is not a drop-in replacement for alkaline, NiMH, or multi-cell packs.
Step 1: Inspect Check the pouch for dents, punctures, or swelling, and check the leads and connector for damage. Do not use a damaged pack.
Step 2: Verify Polarity 2-pin JST pinouts are not standardized between manufacturers. Compare the red (+) and black (-) leads against your device’s battery port markings before plugging in. Reversed polarity can destroy your device instantly.
Step 3: Connect Seat the connector straight into the port. Grip the plastic housing, not the wires.
Step 4: Charge The battery ships at approximately 30% charge, so charge it fully before first use. Use a single-cell lithium charger set to 4.2V or your device’s built-in LiPo charging circuit. Charge at 0 to 45°C, on a non-flammable surface, and stay nearby during the first charge.
Step 5: Mount Mount the pack flat, away from regulators and other heat sources, sharp edges, and screws. Leave a little room in the enclosure and don’t clamp the pouch tight.
Step 6: Store For storage longer than a few weeks, keep the pack partially charged (about 3.8V) in a cool, dry place.
PRO TIP: Measure the pack voltage with a multimeter when it arrives and note it. If your build ever acts strange, a five-second voltage check tells you whether it’s the battery or everything else.
▌DEBUG LOG – TROUBLESHOOTING
ISSUE: Device won’t power on with the battery connected. FIX: Check polarity first. Then measure the pack voltage at the connector. Near 0V usually means the protection circuit tripped after a deep discharge, and connecting a charger resets it. If it still reads 0V after a few minutes on charge, stop using the pack.
ISSUE: Connector doesn’t fit. FIX: 2-pin battery connectors come in several pitches (2.0mm PH, 1.25mm, 1.0mm SH are common). Compare your device’s port with the pack’s connector. Don’t force it or modify the connector unless you’re experienced with lithium wiring.
ISSUE: Charger reports full immediately or won’t charge. FIX: Reseat the connector and check for a loose crimp or broken lead. Confirm the charger is a single-cell 3.7V/4.2V lithium charger.
ISSUE: Runtime is shorter than expected. FIX: High current draw (WiFi transmit, bright displays, LEDs) and cold temperatures reduce usable capacity. Capacity also declines naturally over hundreds of cycles.
ISSUE: Device browns out or resets under load. FIX: The pack may be near empty, or the load is spiking harder than the pack can deliver. Recharge and retest. If it continues, add bulk capacitance near the regulator input or reduce peak current draw.
ISSUE: Pack is swollen, hot, leaking, or smells sweet or chemical. FIX: Stop immediately. Disconnect it if you can do so safely, move it to a non-flammable area, and take it to a battery recycling drop-off.
▌SYS.WARN – WARNINGS, HAZARDS & DISCLAIMERS
Lithium Battery Hazard. Lithium polymer batteries can catch fire, vent, or explode if punctured, crushed, short-circuited, overcharged, or overheated. Misusing or mishandling lithium batteries can cause serious personal injury, property damage, or death. The user must understand how to handle lithium batteries safely before purchase.
Polarity. Connector pinouts vary between manufacturers. The user is responsible for confirming correct polarity before connecting. Reversed polarity can permanently damage the connected device.
Charging. Charge only with a single-cell lithium charger rated for 4.2V or your device’s built-in LiPo charging circuit. Never use NiMH, NiCd, or lead-acid chargers. Charge on a non-flammable surface and never leave batteries charging unattended.
Short Circuit. Never short the battery leads. Keep the connector covered when not plugged in and away from metal objects. Never store a loose battery in a pocket, purse, or bag.
Physical Damage. Do not puncture, bend, crush, cut, or deform the pouch. Do not solder directly to the cell or remove the protection circuit. Do not use a battery that is damaged, swollen, or leaking.
Not for Vaping Devices. Do not use with e-cigarettes, vaporizers, or similar devices.
Compatibility. No express or implied guarantee of compatibility with any device is made. Confirm your device’s requirements and connector polarity before use.
Transport Certification. This cell is UN38.3 tested and is shipped at approximately 30% state of charge in line with IATA and US DOT lithium battery shipping regulations. The UN38.3 test summary is available upon request to authorities, carriers, and other parties with a legitimate need.
Shipping Restrictions. Lithium batteries sold without equipment are regulated as hazardous materials. This item ships only to addresses in the 48 contiguous United States, by ground service. It cannot be shipped internationally, by air, or to Alaska, Hawaii, or US territories.
Not a Toy. Keep out of reach of children and pets.
Disposal. Do not dispose of in household trash or fire. Recycle at a battery collection or drop-off point in accordance with local regulations.
Resellers. Resellers must forward all warnings to all customers for their reference and safety.
Disclaimer. This product is sold “as-is” for use by qualified individuals. Use of lithium batteries is at your own risk. Rabbit-Labs LLC is not responsible for damage resulting from incorrect polarity, improper charging, modification, or physical abuse. Rabbit-Labs LLC makes no warranty, express or implied, regarding fitness for a particular purpose. Maximum liability shall not exceed the purchase price of the product.
© Rabbit-Labs LLC. All rights reserved. The Rabbit-Labs name and logo are trademarks of Rabbit-Labs LLC.
