Widex announces the world’s first battery-free hearing aid



Working on a Nose charger that does both. The truly talented can stick with the original.


I already sleep each night and remember to take my HAs off and open the battery doors.

Changing this this routine to now putting them in a fuel cell “well” for 20s seems hardly a hassle.

this obviously ignores any other disadvantage of whether you can fly/travel easily with the charger, etc.


I seriously doubt that Widex is marketing a technology that one can’t travel with on an airline.


They are permitted.



Yes, if you’re a creature of habit and sleep in the same bed every night where you store your charger. But that takes away the freedom of being able to sleep anywhere you want where the charger is not available, like simply deciding to fall asleep on the sofa after watching a movie, for example. Or deciding to sleep over at someone else’s house last minute without preparing to bring the charger with you ahead of time.

It’s just another chain and ball that takes away some more of your freedom.


I found this article from DTI:


Hydrogen cells on an airplane. What could possibly go wrong? Lol!!!


Methanol based fuel cells are allowed on aircraft.


Too bad they don’t have a slightly longer battery life like the rechargeable Quattro’s. Thirty hours or more on a charge would be good.

Also, as others have pointed out, details on what the expected lifespan is of the fuel cell system in the HA’s, whether it’s something an audi can easily swap out or a device has to be factory-refurbished, what the cost of the charger or fuel caplets will be are still lacking. The article you cite says that a charge is 200 ul (0.2 ml, < 0.2 gm) of methanol so the amounts of flammable liquid or explosive hydrogen would be very small indeed-but presumably the charger base holds at least several methanol charges for both HA’s.

Edit_Update: As pointed out by MDB below, direct methanol fuel cells do no produce hydrogen, only water and carbon dioxide. So my response to chronojockey’s comment about a “hydrogen cell” is superfluous. END_Edit_Update

Hydrogen is a small molecule that diffuses very fast. Explosivity and flammability are only possible with certain ratios of hydrogen to air (or oxygen).

“Now while the explosive limits of hydrogen in air range from about 18 – 60 % the flammable limits are from 4 – 75 % , in oxygen the limit of flammability goes all the way from 4% to 95% read: for practical purposes, hydrogen in oxygen is always at least a flammable mixture. For comparison, gasoline in air is flammable roughly between 1.5 - 7%.”

With such small amounts of hydrogen being relatively slowly generated, unless someone deliberately attempts to make a “bomb,” it’s probably going to be pretty hard to have an explosion - hard to reach the 18% hydrogen % in the hydrogen-air mixture.

(lots of alternative links on Internet)


No thanks from my end. Lithium batteries are bad enough. No need to deal with this problem waiting to happen.


OTH, do you drive? Something like 35,000 people a year are killed in auto accidents. We habituate and take certain risks for granted. (not gonna be me, I’m too good a driver, it’ll be somebody else, and I’ll just swerve out of the way of anything that comes my way, etc.).

So whether or not the technology itself is of any value compared to disposable batteries, that’s another story to be determined by the marketplace and people’s preferences. But if you drive, you’re probably assuming orders of magnitude more risk than by having a miniature fuel cell in your HA’s and the charger in your pocket or bag.

One gallon of gasoline has the energy content of 3 sticks of TNT (7 sticks of dynamite) and you’re driving around usually with about 14 gallons or so with a full tank (~42 sticks of TNT, ~100 sticks of dynamite). Even if the stuff doesn’t explode, it could melt you down to a little puddle of ashes in the road if you’re trapped in your car in an accident and the stuff ignites. Someone mindlessly accepts that risk and worries about the consequences of 0.2 gm of methanol and the relatively teeny amount of hydrogen that will slowly be produced from it over about 20 hours of use???

Edit_Update: As corrected by MDB below, no hydrogen is produced in a direct methanol fuel cell. I was erroneously reacting to chronojockey’s reference to a “hydrogen cell,” which is not correct. Carbon dioxide and water are the products of a direct methanol fuel cell.


Long story short: If humans can figure out a way to avoid imminent death driving around with 14 gallons of gasoline (52,990 mls of the stuff), maybe they can figure out a safe way to go around with 0.2 ml of methanol and the small amounts of hydrogen slowly produced from the stuff. We’re not talking about the Hindenberg here.

Edit_Update: As corrected by MDB below, no hydrogen is produced in a direct methanol fuel cell. I was erroneously reacting to chronojockey’s reference to a “hydrogen cell,” which is not correct. Carbon dioxide and water are the products of a direct methanol fuel cell.


Isn’t H2O what’s given off instead of Hydrogen gas? From what I saw from a quick Google, H+ was an intermediate product, but water was the endpoint of the reaction.


You’re right, MDB. I was just (mindlessly) going off chronojockey’s “hydrogen cells on an airplane” reference.

Here’s a pretty good discussion of methanol-powered fuel cells:

Says that you’re allowed to carry up to 200 ml of methanol on an airplane in a fuel cell cartridge, up from the 100 ml general carry-on limit for methanol (if I read it right while trying to cook at same time!).


Precisely what I was thinking! Shades of the exploding Samsung NOTE!

Aside from this amazing methanol fuel cell powering the aids, the BUG in me has to ask: how do these aids perform in NOISY places?

Cart: get behind HORSE.


As prodigyplace points out, fuel cells containing up to 200 ml of methanol have been permitted on aircraft since 2008. So we’re just behind the times on what’s considered safe (like your car with 14 gallons of gasoline in it, = 100 sticks of dynamite).


Since this is only a CES 2019 announcement, not scheduled to appear 'til this summer, we have only the speculative cart to kick the tires on. The horse has yet to appear and since nothing special is claimed for noise, noise is probably still that tough problem that no one, including lots of folks outside the HA industry, has been able to lick adequately.


Since water is a byproduct where does that go? I doubt the aids leak water.


I think the water (and unused methanol from the previous charge) gets flushed out when the fuel cell in an HA gets recharged with fresh methanol.


I wear the Evoke 440, the platform which uses the fuel cell. They’re fantastic. Nothing else like them. I use the regular battery version though and have no interest in rechargeables.


I’m guessing the water is released a molecule at a time as water vapor.