C Batteries

C Batteries: How to Choose the Right Type for Your Device

C batteries (also called size C, IEC "14"; approx. 26.2 × 50 mm) power medium-drain devices like flashlights, toys, lanterns, radios, and some musical instruments. Most consumer C cells are 1.5 V primary (single-use) or 1.2 V NiMH rechargeable. Picking the right chemistry determines runtime, cost, and reliability.

Quick Comparison

Type (IEC)	Voltage	Typical capacity	Shelf life	Best for	Notes
Alkaline (LR14)	1.5 V	~7000–8000 mAh (low–moderate drain)	5–10 years	Emergency kits, lanterns, toys used occasionally	Inexpensive; may leak if left discharged or stored hot
NiMH Rechargeable (HR14)	1.2 V	~3000–6000 mAh	LSD types retain ~70–85% after 1 year	Frequent use, motorized toys, instruments	Recharge hundreds of times; needs a NiMH C-capable charger
Zinc-carbon (R14)	1.5 V	~3000–4000 mAh	~2–3 years	Very low-drain devices (simple radios, clocks)	Lowest cost; shortest runtime; higher leak risk
Specialty Lithium C-size (e.g., ER26500)	3.6 V	High, varies	Long	Industrial/specialized equipment	Not a drop-in replacement for 1.5 V devices; check device specs

Which C Battery Should You Buy?

Alkaline (most households)

• Use if: You need long shelf life for emergency kits, flashlights, radios, or toys used occasionally.
• Avoid if: You cycle the device daily or have high-drain motors that flatten cells quickly.

NiMH Rechargeable

• Use if: The device is used often (weekly/daily), draws higher current, or you want lower long-term cost and waste.
• Avoid if: The device sits for months between uses and you don’t have low-self-discharge (LSD) NiMH.

Zinc-carbon

• Use if: Cost is critical and the device is very low drain.
• Avoid if: You expect long runtime, high current, or long storage life.

Real-World Runtime Estimates

Actual runtime depends on device current draw, temperature, and cell quality. Approximate figures at room temperature:

• Lantern at 100 mA: Alkaline 60–80 hours; NiMH 40–50 hours; Zinc-carbon 25–35 hours
• Flashlight at 250 mA: Alkaline 20–25 hours; NiMH 16–18 hours; Zinc-carbon 8–12 hours
• Motorized toy averaging 800 mA: Alkaline 4–6 hours; NiMH 5–7 hours; Zinc-carbon 2–3 hours

Buying Checklist

• Match chemistry to use: Alkaline for storage and occasional use; NiMH for frequent use; avoid zinc-carbon unless very low drain.
• Check device guidance: Some manuals specify “alkaline only” or recommend rechargeables.
• Capacity matters: Higher mAh generally means longer runtime at similar loads; expect lower effective capacity at high currents for alkaline.
• Temperature: For cold weather, NiMH typically holds voltage better than alkaline below freezing.
• Charger fit: If buying NiMH, ensure your charger supports C size and NiMH chemistry—many AA/AAA chargers do not.
• Beware of adapters: AA-to-C sleeves work only for low drain and drastically reduce runtime.

Rechargeable Tips

• Prefer low-self-discharge (LSD) NiMH C cells if devices sit unused for weeks to months.
• Charge with a smart NiMH charger that supports C cells; avoid “timed only” chargers for large capacities.
• Break-even: Frequent users typically recoup the cost of NiMH within a few cycles compared to buying multiple sets of alkaline.

Storage and Safety

• Store cool and dry (50–77°F / 10–25°C). Avoid heat and direct sun; do not freeze.
• Keep in original packaging or a case to prevent short circuits.
• Replace all cells in a device at the same time; never mix old with new or different chemistries.
• Do not attempt to recharge non-rechargeable batteries.
• Recycle where available; check local programs for single-use and rechargeable batteries.

Compatibility Notes

• Voltage: NiMH C cells are 1.2 V nominal (vs. 1.5 V alkaline). Most devices tolerate this, but some may run slightly dimmer or shorter.
• Specialty lithium C-size cells (often 3.6 V) are not substitutes for standard 1.5 V C batteries unless your device specifically supports them.

FAQ

Are rechargeable C batteries safe for all C-battery devices?
Usually yes, but check the manual. The 1.2 V nominal of NiMH is acceptable for most devices; a few products expect 1.5 V only.

How long do C batteries last in storage?
Alkaline: typically 5–10 years; NiMH LSD: good performance for 1–3 years with periodic top-ups; zinc-carbon: about 2–3 years.

Can I fly with C batteries?
Yes. Keep spares in carry-on with terminals covered. Rechargeables should be carried, not checked, per many airline policies.

Why did my batteries leak?
Heat, deep discharge, or mixing old/new cells can cause leakage, especially with zinc-carbon and alkaline. Remove cells from devices stored long term.

Do “1.5 V rechargeable C” batteries exist?
Some regulated lithium options exist but require their own chargers and may behave differently. For broad compatibility, stick with NiMH for rechargeables.