Can’t figure out why your old iPhone’s battery has degraded over time? Read on.

John Poole, founder of Primate Labs, the company behind the popular benchmarking platform Geekbench, earlier this week claimed that iPhone 6 and iPhone 7 phones comes with a software-based issue wherein Apple allegedly throttles the performance in order to extend the battery life.

Battery life has been one of the major painpoints for iPhone users. If you have been using an older iPhone, you might have noticed a drop in battery life over a period of time. A common conception is that newer versions of iOS aren’t that well optimised for older iPhones, and hence drain battery life. While it may be true to some extent, there are way too many factors involved in determining the battery life of a phone.

While there are various workarounds such as using power mode and disabling radios and location services to extend the battery life, you need to understand the fundamentals of how batteries on the iPhone work.

Apple’s iPhones use lithium-ion battery which tends to degrade after some time and have a limited lifespan. For instance, Apple iPhones have 500 complete charge cycles whereas Apple Watch has 1,000 complete charge cycles before they start to deteriorate.

Now, here’s what you need to understand about the charge cycles. A charge cycle is generally referred to the process of charging a phone to 0% to 100%. This does not mean that if you put your phone on charge at 60% and then add another 40% it will be counted as two separate cycles. In fact, they combine for one complete battery charge cycle.

On moderate to light usage, an iPhone may last one day before hitting the critical 15% or 20% battery. So, if you charge your iPhone once a day, you can continue to do so for next 500 days (roughly one and half years).

Apple Complete Charge Cycles
  • iPhone: 500 complete charge cycles
  • Apple Watch : 1,000 complete charge cycles
  • iPad: 1,000 complete charge cycles
  • iPod: 400 complete charge cycles.
  • MacBook: 1,000 complete charge cycles

So, what happens next when you complete 500 complete charge cycles? According to Apple, the iPhone battery retains at least 80% of their original capacity for a high number of charge cycles, which varies depending on the product.

“There’s no need to let it discharge 100% before recharging. Apple lithium-ion batteries work in charge cycles. You complete one charge cycle when you’ve used (discharged) an amount that equals 100% of your battery’s capacity — but not necessarily all from one charge,” Apple explains on its website.

“For instance, you might use 75% of your battery’s capacity one day, then recharge it fully overnight. If you use 25% the next day, you will have discharged a total of 100%, and the two days will add up to one charge cycle. It could take several days to complete a cycle. The capacity of any type of battery will diminish after a certain amount of recharging.”