Panasonic AAA Eneloop

Panasonic Eneloop AAA Rechargeable Batteries (NiMH, 800 mAh)

Panasonic Eneloop AAA are low self-discharge NiMH batteries designed for everyday and professional use. They ship ready to use, hold charge well in storage, and deliver consistent power across a wide temperature range.

When to choose these

• Daily-use devices: TV remotes, toys, wireless keyboards/mice, LED penlights/headlamps.
• Cordless phones that specify AAA NiMH cells (common for DECT handsets).
• Cold-weather use (down to -4°F / -20°C) where alkalines sag under load.
• To lower battery waste and running costs vs. single-use alkalines.

When to consider alternatives

• Ultra-low-drain devices used a few times per year (e.g., seldom-used emergency remotes): primary lithium AAA (e.g., Li-FeS2) offer longer shelf life but are not rechargeable.
• Devices that require 1.5 V per cell or specify “alkaline only”: some older equipment may not recognize 1.2 V NiMH; check the manual.
• Devices that physically require AA or specialty lithium cells: choose the specified size/chemistry.
• Do not use 10440 Li-ion (3.7 V) as a replacement—voltage is incompatible unless the device explicitly supports it.

Typical runtime examples

Real-world runtime varies by device draw, settings, and temperature. Example estimates per 1 cell (800 mAh):

• Wireless mouse at ~3 mA average: about 250–300 hours (8–12 weeks of typical office use).
• TV remote (very low average draw with bursts): months to a year+ per set.
• LED penlight: ~50 mA low mode ≈ 16 hours; ~150 mA medium ≈ 5 hours; ~300 mA high ≈ 2–2.5 hours.
• Cordless phone handset (pair of AAA cells): similar or better talk/standby time vs. stock 550–750 mAh packs.

Charging and care

• Use a smart NiMH charger with delta-V/temperature monitoring. Avoid Li-ion/NiCd-only chargers.
• Recommended charge rates: 0.2–0.5C. For 800 mAh cells, that’s ~160–400 mA (about 5–6 hours at 0.2C, 2–3 hours at 0.5C; plus top-off as needed).
• Charge between 32–104°F (0–40°C). Do not charge below freezing.
• Store cool and dry, ideally 40–60% charged. Top up every 6–12 months if stored long term.
• Replace cells as a set in multi-cell devices; do not mix old and new or different brands/capacities.

Specifications

Chemistry	Nickel-Metal Hydride (low self-discharge)
Size	AAA (IEC R03)
Nominal voltage	1.2 V
Typical capacity	800 mAh (minimum 750 mAh)
Cycle life	Up to 2,100 recharges (with proper charging)
Charge retention	Up to 70% after 10 years of storage at 68°F/20°C
Operating temperature (discharge)	-4°F to 122°F (-20°C to 50°C)
Charging temperature	32°F to 104°F (0°C to 40°C)
Dimensions	Ø10.5 × 44.5 mm
Weight	Approx. 13 g per cell
Environmental	No added mercury or cadmium; factory pre-charged using renewable energy

Pros and cons

• Pros: Long cycle life, excellent shelf retention, reliable in cold, lower total cost vs. disposables.
• Cons: 1.2 V nominal may not suit devices calibrated strictly for 1.5 V; requires a proper NiMH charger.

Compatibility notes

• Safe replacement for standard AAA batteries in devices that support rechargeables.
• For cordless phones, only use if the handset or base specifies AAA NiMH cells. Never place non-rechargeable cells in a charging cradle.
• If a device shows “low battery” early with NiMH, it may be calibrated for 1.5 V; if supported, disable “alkaline only” mode or choose primary lithium/alkaline.

FAQ

Will these work in a device that says “alkaline only”?

Not recommended. Some devices require the higher 1.5 V of alkalines. Check the manual; if rechargeables are allowed, Eneloop AAA are a good fit.

Do NiMH batteries have memory effect?

NiMH memory effect is minimal. Normal use is fine; an occasional full discharge/charge can help the charger gauge capacity but is not required routinely.

How do I know the cells are aging out?

Noticeably shorter runtime, cells heating quickly during charge, or measured capacity dropping below ~60% of rated are signs to replace.

Can I mix these with other brands or older cells?

Avoid mixing. Use matched cells of the same brand, capacity, and age in the same device for best performance and safety.

What charger should I use?

Use a smart NiMH charger that terminates on -ΔV and/or temperature rise and offers individual slot monitoring. Panasonic smart chargers are a safe match.