Why This Bundle
The LG HE4 is the successor to the popular HE2, carrying the same 2500mAh capacity and 20A continuous discharge rating with improved cell consistency. A cell this capable deserves a charger that treats it right. This bundle pairs 2 genuine LG INR18650-HE4 Flat Top batteries with the NITECORE UI2 — a compact, USB-C powered charger that automatically selects the right charging mode and includes trickle charging and over-discharge protection. Everything you need to charge and maintain your cells, ready out of the box.
LG INR18650-HE4 (Flat Top) Specifications
| Item |
Spec |
| Model |
LG INR18650-HE4 (Flat Top) |
| Nominal Capacity |
2500mAh |
| Nominal Voltage |
3.6V |
| Max Continuous Discharge |
20A |
| Max Charge Voltage |
4.2V±0.05V |
| Max Charge Current |
4000mA (fast charge) |
| Discharge Cutoff Voltage |
2.5V |
| Chemistry |
INR (Lithium Nickel Manganese), high-drain |
| Cell Size |
18650 (approx. Φ18.28mm × 64.98mm) |
| Terminal Type |
Flat Top — level positive terminal, suited for devices requiring full-surface contact |
| Typical Use |
Power tools, high-output flashlights, e-bikes, hoverboards, and other high-drain applications |
Note: This is a high-drain, unprotected cell — avoid mixing with batteries of a different brand, model, or charge state, and inspect the wrap for damage before every use to prevent short circuits.
The Charger: NITECORE UI2
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USB-C input: charge from any 5V power bank, solar panel, or USB adapter — great for travel and outdoor use
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Automatic CC/CV Charging: intelligently selects the most suitable charging mode for each cell
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Independent Dual-Bay Control: each of the 2 bays charges independently without affecting the other
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Trickle Charging: automatically switches to 100mA trickle mode for batteries below 2.9V, then up to 1000mA standard charging above 2.9V
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Over-Discharge Activation: automatically detects and reactivates over-discharged protected Li-ion cells
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Multiple Safety Protections: reverse-polarity/short-circuit protection, intelligent temperature control, and overcharge protection
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Ultra-Compact & Lightweight: just 79.5g, 125.5 × 59.5 × 32.1mm
NITECORE UI2 – Supported Battery Types & Voltage
Charges 3.6V/3.7V Li-ion/IMR batteries, including the LG HE4 (18650) in this bundle:
10340, 10350, 10440, 10500, 12340, 12500, 12650, 13450, 13500, 13650, 14430, 14500, 14650, 16500, 16340 (RCR123), 16650, 17350, 17500, 17650, 17670, 18350, 18490, 18500, 18650, 20700, 21700, 22500, 22650, 25500, 26500, 26650
Output voltage: 4.2V±1% Output current: up to 1000mA per bay (max 2 bays simultaneously)
Compatibility Notes
The UI2's charging bays are open-ended, allowing Flat Top batteries to seat securely without any adapter. LG HE4 Flat Top cells measure about 65.0mm, well within the UI2's compatible battery range.
Note: The HE4 supports fast charging up to 4000mA, but the UI2 charges at up to 1000mA per bay. This means slower charging than a dedicated high-current charger, but with a gentler, longer-lasting charge cycle that's easier on the cell.
What's Included
- LG INR18650-HE4 Flat Top Battery × 2
- NITECORE UI2 Charger × 1
- USB-C Charging Cable × 1
- User Manual × 1
Safety Tips
- Store batteries in a proper case, keeping them away from loose metal objects to prevent short circuits
- Never disassemble, puncture, burn, or submerge the batteries
- Charge only with a genuine, compatible charger such as the NITECORE UI2
- The HE4 is an unprotected, high-drain cell intended for compatible, purpose-built devices — do not use it in unauthorized or modified equipment
- Never discharge below 2.5V or charge above 4.2V
FAQ
Q: Can the NITECORE UI2 charge LG HE4 Flat Top batteries safely? A: Yes. The UI2 automatically selects the optimal CC/CV charging mode for Li-ion cells like the HE4, with a 4.2V±1% output voltage and up to 1000mA per bay.
Q: Will Flat Top batteries sit properly in the UI2 charger bays? A: Yes. The UI2's open charging bays are designed to accommodate both Flat Top and Button Top cells without any adapter or modification.
Q: Can I charge both batteries at the same time? A: Yes. The UI2 has 2 independent bays, each capable of up to 1000mA, and one battery's charging status does not affect the other.
Q: Can I power the UI2 with a power bank while traveling? A: Yes. The UI2 has a USB-C input and works with any 5V power source, including power banks, solar panels, and USB wall adapters.
Q: What happens if an HE4 battery has over-discharged? A: The UI2 includes an over-discharge activation feature that automatically detects and reactivates protected Li-ion cells that have dropped too low from storage or improper use. Note that the HE4 is an unprotected cell, so always avoid discharging it below 2.5V in the first place.
Q: Is 20A continuous discharge safe for everyday devices? A: No — the HE4 is a high-drain cell intended strictly for devices specifically engineered for high continuous discharge, such as certain power tools, and high-output flashlights. Always check your device's battery requirements before use.
Q: How does the HE4 compare to the HE2? A: Both share the same 2500mAh capacity and 20A continuous discharge rating. The HE4 is LG's later revision, generally offering improved manufacturing consistency over the original HE2.
Q: How long does it take to fully charge an HE4 in the UI2? A: Since the UI2 charges at up to 1000mA per bay while the HE4 supports fast charging up to 4000mA, expect a longer charge time than a high-current dedicated charger — typically several hours for a full charge, depending on the starting charge level.
Q: What's in the box? A: 2 LG INR18650-HE4 Flat Top batteries, 1 NITECORE UI2 charger, a USB-C charging cable, and a user manual.
