PowerOne ACCU Plus Size 312 Rechargeable Hearing Aid Batteries

What it is

Nickel-metal hydride (NiMH) rechargeable batteries for hearing aids that use size 312 (brown). Designed to work with PowerOne chargers for users who want reusable power instead of disposable zinc‑air cells.

Quick specs

Chemistry	NiMH (rechargeable)
Nominal voltage	1.2 V
Typical capacity	~21 mAh
Size / code	312 (brown) — 7.9 mm Ø × 3.6 mm H
Recharge life	Up to ~800 cycles with proper charging
Charge time	About 2.5–5 hours in a compatible PowerOne charger
Expected runtime	~6–12 hours per charge (varies by hearing aid current draw and streaming)
Chargers	PowerOne PocketCharger or Pen Charger (with 312 insert)

When to choose these

• Use if you wear size 312 hearing aids that explicitly support NiMH rechargeables and PowerOne chargers.
• Good for moderate daily use, office or classroom settings, and users who can charge mid‑day if needed.
• Preferable if you want to reduce disposable battery waste and ongoing replacement purchases.

Avoid or consider alternatives if

• You require all‑day wear (12–18 hours) with frequent Bluetooth streaming — zinc‑air 312 disposables or a hearing aid with built‑in Li‑ion may be a better fit.
• Your device uses a ZPower silver‑zinc system, an Oticon/OEM ZPower variant, or a built‑in dock/charger — these are not compatible with PowerOne NiMH cells.
• Your manufacturer does not approve rechargeable cells — check your manual or ask your hearing care professional.

Compatibility and setup

Only use with hearing aids designed for size 312 rechargeables and with PowerOne chargers. Do not attempt to recharge zinc‑air batteries. If your hearing aid originally shipped with disposable 312 cells and no mention of rechargeables, verify compatibility before purchase.

• Fits common ITC (in‑the‑canal) and half‑shell devices that accept size 312 cells.
• Not for aids with sealed Li‑ion packs or ZPower charging doors.
• Use the correct 312 insert in the PocketCharger or Pen Charger for proper contact and charging.

Real‑world runtime expectations

Runtime depends on your hearing aid’s average current draw (mA) and streaming time. A simple estimate:

Estimated hours ≈ 21 mAh ÷ average mA draw

• Basic digital aid (~1.8 mA): about 10–12 hours
• Wireless features (~2.5 mA): about 7–9 hours
• Frequent streaming (~3.0 mA): about 6–7 hours

Plan a mid‑day top‑up if you stream often or use high‑power programs.

Charging and care

• Charge daily. Partial charges are fine; NiMH has minimal memory effect.
• Allow 2.5–5 hours for a full charge depending on charger and cell condition.
• Keep contacts clean and dry; wipe with a soft dry cloth if needed.
• Store at room temperature; avoid heat, freezing, and high humidity.
• Replace the pair when daily runtime shortens noticeably despite full charges (often after a few hundred cycles).

Pros and cons

• Pros: Reusable, lower ongoing waste, predictable performance for moderate wear, works with compact chargers.
• Cons: Lower capacity than zinc‑air 312; may not cover a full day with heavy streaming; requires dedicated charger and compatibility.

Safety and recycling

• Keep away from children and pets; if swallowed, seek medical help immediately.
• Do not short‑circuit, puncture, or expose to fire.
• Recycle used cells through battery recycling programs; do not dispose of in household trash where restricted.

FAQ

Will 1.2 V NiMH work in place of 1.45 V zinc‑air?

Many compatible 312 hearing aids regulate voltage and work fine with 1.2 V NiMH, but not all do. Always confirm in your manual or with your audiologist.

Can I mix one rechargeable and one disposable in the same aid?

No. Never mix chemistries in the same device. You may use different chemistries in left vs. right ears if each device is compatible and managed separately.

How many cycles will I get?

Up to roughly 800 charges is possible under ideal conditions. Actual life varies with depth of discharge, temperature, and charging habits.

How do I know the cells are wearing out?

Signs include reduced daily runtime, requiring more frequent charges, or chargers indicating errors. Replace as a pair for consistent performance.

Are these compatible with ZPower chargers?

No. PowerOne NiMH cells are not compatible with ZPower silver‑zinc systems or their charging doors.