Alkaline (Regular) |
Standard, widely available disposable batteries. |
6–12 months |
Low |
Inexpensive, easy to find. |
Requires frequent replacement, risk of forgetting. |
Lithium 9V |
Long-lasting disposable battery designed for low-drain devices like smoke alarms. |
Up to 10 years |
Medium to High |
Long lifespan, reduces maintenance. |
Higher upfront cost, not rechargeable. |
Rechargeable NiMH |
Reusable batteries that can be recharged multiple times. |
1–2 years per charge cycle |
Medium to High |
Eco-friendly, cost-effective over time. |
Requires regular recharging, lower capacity. |
Built-in Lithium |
Integrated batteries in sealed units, typically part of 10-year alarms. |
10 years (non-replaceable) |
Included with alarm |
Zero maintenance, no need to buy batteries. |
Entire unit needs replacement after 10 years. |
Carbon-Zinc |
Older, inexpensive disposable batteries. |
3–6 months |
Very Low |
Cheapest option. |
Short lifespan, unreliable performance. |