# Xiaomi touts Hypercharge 200W charging tech, claims 4,000mAh battery goes from 0 to full in 480 seconds

Chinese mobile maker Xiaomi has demoed its latest charging tech, dubbed HyperCharge. Xiaomi claims its tech allows a 200W charger to fully replenish a 4,000mAh battery in eight minutes. HyperCharge, the company also claimed, could deliver a 50 per cent charge in three minutes. To preserve battery health, charging speeds …

1. #### Stupid lab tricks

This is great, but when you charge a Li-ion battery at faster than 1C, it roasts that puppy, and battery life goes straight into the trash.

> To preserve battery health, charging speeds typically decelerate as a device reaches full capacity

Not true. Charging speeds typically decelerate because the Battery Management System stops charging cells with higher voltages to let lower charged cells catch up and level out mismatches.

To preserve battery health, you simply don't charge faster than 1C, especially when the battery is hot.

1. #### Re: Stupid lab tricks

If you're going to pick holes in things because you're so clever, at least have the courtesy to explain to us mere mortals what "1C" actually means, given there's no mention of such a unit anywhere in the article??

1. #### Re: Stupid lab tricks

Using a little Google Foo I discovered that it is the rate to charge a battery of 1Ah (1000mAh).

Which means a 4Ah battery would literally be 4 hours to charge.

Note: the little I read on it mentioned that 1Ah should be able to discharge at 1A for 1h.

1. #### Re: Stupid lab tricks

Thinking my above sounded a little weird I investigated some more.

C=Capacity[Ah]/1[ℎ] (See IEC_61434)

1. #### Re: Stupid lab tricks

er... so "C" is another way of saying Ampere? [1] !C is charging at 1 amp?

Thank goodness, that old "amps" unit was way gnarly and old-fashioned.

+

[1] No, surely I must be wrong. I must've misunderstood. Surely...?

1. #### Re: Stupid lab tricks

>er... so "C" is another way of saying Ampere? [1] !C is charging at 1 amp?

No, its related to battery capacity.

The modelling community learned very quickly about charging larger, high current, lithium batteries because those batteries quickly got a reputation for being a fire risk. Even with modern intelligent charging systems is normal practice to charge these things outdoors or in a flameproof container. Boeing were slightly slower on the uptake with their 787, it used high capacity lithium batteries and the planes suffered from fires before they were able to get charging and containment under control. (Lithium batteries are now banned from aircraft holds as a fire risk.)

I'd guess that this phone's got all the safety bells and whistles on it but I won't be getting one -- its still a fire risk. You also have to ask yourself why a phone needs a 4AH battery and frequent charging -- if the phone gets hot during use then that's an issue.

2. #### Re: Stupid lab tricks

1C is the charging/discharging rate that will fill/empty the battery in one hour. So for a 4Ah battery, it's a current of 4A.

2. #### Is this really useful for anyone?

What's the actual use case here? I can see it for EVs, but not really for phones.

If I'm going out for the day, then I'll stick the phone on charge in advance of leaving the house. If I have to leave first thing, I'll stick it on overnight, and it can trickle top up while I sleep.

I don't really see a use case, at least not for myself, where 200W charging would be useful!

Even if I get an unexpected call to head off somewhere at short notice, my now rather ancient OnePlus 3 can stick a decent amount of charge (about 30-40%) in the phone in the 10-15 min it would likely take me to grab a shower and throw some clothes on, and that's assuming I'm on foot. If I'm in the car, I can charge it there.

This just seems to be a case of bigger number = better marketing, i.e. I can pee higher than you!

Anyone out there who'd find it actually useful? The charging, not the pee ;-)

Icon: What could possibly go wrong with 200W charging :-)

1. #### Re: Is this really useful for anyone?

Numbers sell phones

Numbers users understand: Camera megapixies, big = good, Charging time, small = good.

2. #### Re: Is this really useful for anyone?

Yep. Solution looking for a problem.

I can remember my first analogue mobile, nearly 30 years ago. 8hr battery life (so long as you didn't use it much) and 8 hrs to recharge. 10 minute charging would have been great.

But now? My Android Honor thingy can run for a couple of days on a full charge (depending on usage) and fully recharges from 20% in under an hour. I charge it at night.

And it doesn't need a separate charger - just a standard USB-C plug.

1. This post has been deleted by its author

3. #### Re: Is this really useful for anyone?

"What's the actual use case here?"

Serious?

Examples:

Airport, phone low on battery, charged to full while grabbing a cup of tea.

Festival, phone charged at a (paid for) charging station at a fraction of the cost it would normally cost the customer because it took a fraction of the time. Business happy because they're getting 4-6 times as many customers.

Public transport, phones charged while waiting for (or on) bus/train and passengers happy because they can read el Reg rather than buy one of those uninformed, inferior newspapers.

Essentially, this is attractive to people that use their phone sufficient to run out of battery and don't have the ability to charge it for a few hours.

1. #### stupid examples

Those places won't have some random company's proprietary 200 watt charger available, so you'd have to carry that 200 watt brick with you. If you're going to carry a charging brick, you might as well carry instead a battery pack of equal size/weight which would hold several full charges worth of juice to keep your phone topped up.

If you want something that can charge at insane rates wouldn't you rather it be a \$30 battery pack that you can easily replace if you wear out the battery prematurely from fast charging than a phone that costs far more and is a far bigger problem for you if it suddenly goes up in flames?

1. #### Re: stupid examples

DS999 whined: "stupid examples

Those places won't have some random company's proprietary 200 watt charger available"

Sigh, it's a technology demonstration, not a product about to be released.

I don't use the fast charging on my phone but I can think of reasons a faster charging battery would be useful, especially in conjunction with battery improvements that reduce the disadvantages.

You and the other people saying it's pointless are just an example of the "I don't need it so no one else does" crowd.

1. #### Re: stupid examples

How about answering my objections to it - that if you have to carry a big charging brick (because you can't make a 200 watt charger small) then that would be a stupid decision versus carrying a powerpack of equivalent size/weight which would be capable of multiple full charges of your phone. Not only that, but you wouldn't have to find an open outlet in an airport or wait in line to use a charging station at a festival. Why in the world would anyone carry a 200 watt charger around when it has so little utility compared to a powerpack?

4. #### Re: Is this really useful for anyone?

I don't see 200W charging to be useful for anything else than requiring a battery swap every year, and with how restrictive and anti-repair companies are, I doubt the production model they include this feature on will allow it without voiding your warranty, and nor will battery health be included in the warranty... Like was already stated, just carry a second battery, just like the smart tech user has already been doing since the era of "dumb" flip-phones. I carry one with me to help prop up the dying battery in my smartmobe, and I will continue to carry it when I get my new device...

Speaking of new device, I'm getting one of these, something with a real defining feature: https://www.indiegogo.com/projects/astro-slide-5g-transformer

The preproduction unit is almost fully functional. I joked when I saw it that it could replace my trusty X220T for my ultra-portable computing needs, and I think that may actually come to be.

3. #### Domestic supply issues

Is anyone thinking about the peak power demands on a domestic property these days?

I was warned by the electricition on my new house that as it has no gas supply, the heating is electric, the hot water is electric, the cooker is electric plus all the normal devices that we have. In addition we have some elctric showers and a car charging point. Basically despite this being a new house we will have to be careful not to run too many power hungry appliances at the same time. Our house is also pretty much as efficient as you can be without haveing a specialised eco home.

A domestic (UK) single phase supply is not really enough when you remove gas (as it the uk gov plan) and add in electric vehicles. We didn't even have the option for a 3 phase if we'd been willing to pay. The nearest supply was several miles away.

1. #### Re: Domestic supply issues

"Is anyone thinking about the peak power demands on a domestic property these days?"

No. Electric cars are new, but everything else you mention has been standard for a long time. Sure, gas heating and hot water are more common, but electric is really quite common as well. There are plenty of old houses* with an electric immersion heater for water and a few electric heaters instead of central heating. Electric ovens have also been standard for a long time. As have toasters, fridges, freezers, TVs, computers, and so on. And of course, not too long ago it was normal to have a few kW of lighting in most houses. A 200W phone charger wouldn't even be noticed.

Electric cars could be a problem, but as things stand the grid as a whole couldn't cope with every house having a car to charge, so that's something that needs to be solved at a much higher level than individual domestic electrics.

* And when I say old, the flat I used to live in was built in the 1980s with no gas, as was the entire estate it was part of.

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