I know these are currently out of fashion but I'm still thankful they exist.
Let's remind ourselves of devices that use(d) these standardized batteries:
* Toys
* Digital cameras
* Torches
* Gadgets like fans
* Wireless keyboards
* TV remotes
Thanks to having a standardized system of batteries,
* You can use the same battery across several devices. This is a no brainer but it's very practical.
* Batteries can charge quicker thanks to being put in a dedicated charger and not being limited by USB cables. (But yes I concede that USB has been updated for faster charging over the years)
* Devices don't have down time when their battery is charging. To charge, the battery is removed from the device and can immediately be replaced with a fresh one.
* You'll never have to trash a device due to an expired battery. Just buy a replacement. And building on this...
* Any improvements in future battery technology can be retro-fitted into your existing devices. And there is a high incentive for future improvement, because...
* An accessible (due to easy replacement) and large (due to many devices) battery market is very attractive to competition.
If you look at the pros I listed, they all happen to be things that would be very useful for electric cars. So I think it would aid the adoption of electric cars if their batteries were standardized too.
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