The short answer
If a device sits unused for months, or if it's something where reliable power is safety-critical, stick with quality alkaline or lithium disposables. For anything you use daily and recharge regularly, rechargeables will save you money and reduce waste significantly.
The real cost comparison
Let's use AA batteries in a TV remote as a concrete example. Most remotes need replacement roughly every 6 months with regular use.
TV remote — AA batteries — over 5 years
The maths shifts dramatically once you factor in all the devices in your home. A household running rechargeables across a TV remote, wireless keyboard, mouse, torch, and a couple of kids' toys can easily save £50–£100 per year once the initial charger cost is covered.
Device-by-device guide
| Device | Recommended | Reason |
|---|---|---|
| TV remote | Rechargeable | Used daily, easy to swap, pays back quickly |
| Smoke alarm | Disposable | Most manufacturers advise against rechargeables — safety critical |
| CO detector | Disposable | As with smoke alarms — always use fresh alkaline or lithium |
| Game controller (Xbox, etc) | Rechargeable | High drain, used frequently — biggest savings of any device |
| Wireless keyboard & mouse | Rechargeable | Daily use, low hassle to swap at a desk |
| Car key fob | Disposable | Uses CR2032 coin cell — no rechargeable equivalent for most fobs |
| Wristwatch | Disposable | Uses coin cells, extremely low drain, lasts years per battery |
| Torch / flashlight | Rechargeable | High drain when used, good candidate — especially for regular users |
| Digital camera | Rechargeable | Very high drain — rechargeables outperform disposables here |
| Baby monitor | Rechargeable | Continuous use makes rechargeables significantly cheaper |
| Emergency kit / backup | Disposable | Lithium disposables hold charge for 10–20 years in storage |
| Kids' toys | Rechargeable | Toys can drain batteries rapidly — rechargeables earn back fast |
| Guitar pedal | Either | 9V rechargeables exist but are less common — both work fine |
| Hearing aid | Disposable | Specialist zinc-air cells — follow manufacturer guidance |
| Wall clock | Either | Very low drain — a single alkaline AA can last 2 years |
The best rechargeable batteries you can buy
Not all rechargeables are equal. Cheap own-brand rechargeables can lose charge quickly in storage, perform poorly in cold temperatures, and degrade faster. These are the brands consistently recommended by independent testers.
AA rechargeable batteries
AAA rechargeable batteries
Chargers
The environmental picture
A single Panasonic Eneloop AA can be recharged up to 2,100 times. That means one rechargeable battery can replace over two thousand disposables across its lifetime. The environmental maths is overwhelming — even accounting for the higher energy cost of manufacturing a rechargeable cell, the lifetime carbon footprint is a fraction of the equivalent disposables.
That said, disposable batteries are not inherently bad if used appropriately and disposed of correctly. In the UK, all retailers selling more than a certain quantity of batteries are legally required to provide a battery recycling point. Supermarkets, electronics stores and many councils offer free battery recycling. Never put batteries in general household waste — they contain materials that can leach into soil and water.
When disposable batteries are genuinely better
It's worth being direct about this, because too many guides gloss over it. There are several situations where disposables are the right choice — not just acceptable, but actively preferable.
Safety-critical devices. Smoke alarms and carbon monoxide detectors should use fresh alkaline or lithium disposables. Most manufacturers explicitly state this in their documentation. The concern is that some alarms rely on a voltage drop to trigger the low-battery warning — rechargeables discharge differently and the warning may not trigger reliably. Replace the battery in your smoke alarm once a year regardless of whether it beeps.
Long-term storage. Lithium disposable AA batteries (not to be confused with lithium rechargeable) can hold their charge for 10 to 20 years in storage. This makes them ideal for emergency kits, backup torches, and any device that sits unused for extended periods. Rechargeables will self-discharge over months even when not in use.
Coin cells. Most coin cell batteries — CR2032, LR44 and similar — do not have practical rechargeable equivalents for consumer use. For these, quality disposable alkaline or lithium cells from reputable brands are the correct choice.
Very low-drain devices. In a device that draws tiny amounts of power continuously — a basic wall clock, a simple thermometer — a good alkaline AA can last two to three years. The convenience of not having to recharge may outweigh the cost saving.