You may have read that the capacity of the new Smart Cases for iPhone Xs, Xs Max and Xr has decreased. That’s true. But don’t be angry: they can still store more energy.
This is due to the fact that often only the capacity of a battery is looked at, which is given in mAH (milliampere hours). This indicates how much charge a battery can hold. You can imagine it simplified as the amount of electrons you have at your disposal. This value has actually decreased with the new cases. So the Smart Battery Case for the iPhone Xs comes to 1369 mAH compared to that of the iPhone 6s with 1877 mAh.
Nevertheless, the new variant fits more energy. Why? Because power in watts always consists of voltage in volts and current in amps. In common parlance: it depends not only on how many electrons flow through the wire (ampere) but also how many oomph they have (volt). And here’s where it gets interesting: the new case works with a higher voltage.
- Old Case: 1877 mAH times 3,8 Volt are 7,13 Wh
- New Case: 1369 mAh times 8.7 Volt are 11.9 Wh
As you can see, fewer electrons fit into the new variant, but each of them has more energy, which means that more energy can be taken from the battery in total. Otherwise it wouldn’t be possible to explain why the talk times with the new batteries are better than with the old battery packs.
So note: yes, the value in mAH indicates the capacity of a battery. But without multiplying this value by the voltage (and then dividing it by 1000) it says not much about the total energy stored in the battery. As in this case: one might think the new variants are smaller – but in reality they work with a higher voltage and contain more energy.
Why have we now calculated 11.9 watt hours for the new case and Apple only states 10.1 Wh on the case? Well, you won’t get all the energy you put into the case out again. Therefore you should always pay attention to the information in watt-hours, which considers this circumstance, so it is the more honest information. You could already observe something similar during the review of the Blitzwolf battery pack.
