iPhone Battery Health Below 80%? It’s TIME to Cash In & Sell It


Replacing the battery won't significantly increase resale value — especially on older models. Most buyers still consider it “used with wear.”Pin

Key Takeaways

  • iPhone battery replacements are expensive and rarely worth it
  • Low battery health doesn’t mean your phone is worthless but the cost of replacing it doesn’t make sense – you’ll get more by selling (especially with newer models)
  • Selling it “as-is” gets you fast cash with zero effort
  • Value barely increases with a new battery anyway

Battery replacements can cost over £100 — and barely boost your phone’s value.

Don’t Waste Money Replacing a Failing Battery

Once your iPhone battery health dips below 80%, you’ll start noticing sluggish performance, random shutdowns, and battery life that barely gets you through lunch.

It’s not quite as annoying as an iPhone with a cracked or broken screen, but it still sucks – especially if you’re a heavy user.

Apple will happily replace the battery — but you’ll pay up to £105 for the privilege. And if you’re using an older model, that’s just not worth it.

Instead of sinking money into a battery replacement, sell your iPhone as-is, pocket the cash, and put it toward your next upgrade—no hassle, no downtime.

Here’s What a Battery Replacement Costs:

  • iPhone 14, 13, 12, 11£105
  • iPhone SE, 8, 7 and older£79
  • Third-party repairs – Cheaper, but often void warranties and use lower quality parts

⚠️ Heads-up: Replacing the battery won’t significantly increase resale value — especially on older models. Most buyers still consider it “used with wear.”

Why Selling As-Is Makes More Sense

Don’t stress if your iPhone’s battery health has dipped below 80%.

It’s a common issue, especially in older models, and you don’t need to replace the battery to sell it.

💡 Pro Tip: Don’t bother going to Apple or a repair shop just to boost battery health — the cost usually outweighs the resale value boost.

Here’s why your low battery iPhone is still worth cash:

  • We factor in battery wear when making offers — we’re used to swapping out old cells.
  • You’ll save time and money by skipping the battery replacement process (which can cost £70 to £100+).
  • You’ll get a decent payout, especially if the screen and body are in good nick.

What’s Your iPhone Worth with a Weak Battery?

Here’s a rough idea of what you can get without doing any repairs:

iPhone Model Battery Health Estimated Recycle Value (UK) Notes
iPhone 13 78% £250–£300 Battery below Apple’s 80% threshold; value reduced for trade-ins.
iPhone 11 Poor battery life £150–£200 Still in demand despite battery issues; lower trade-in value.
iPhone 8 / SE (2020) Weak battery £50–£100 Low resale value; private sales may yield better returns.

Compare that to spending £79–£105 just to improve battery life? Doesn’t make sense financially.

Find out how much you could get for your iPhone with low battery health – we’ll get you a quote within the hour.

FAQ

Is 80% battery health bad for an iPhone?
Yes — Apple considers anything under 80% “significantly degraded.”

Should I replace the battery before selling my iPhone?
No — it won’t increase the value enough to justify the cost.

Can I sell my iPhone with poor battery health?
Definitely. KnowYourMobile accepts them and still offer solid payouts.

How much does a new iPhone battery cost in the UK?
£79–£105 depending on your model — and that’s with Apple.

Will a battery replacement improve performance?
It might, but it’s rarely worth it if you plan to sell the phone soon anyway.

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