Hugh Hetherington Hearing Aid Museum
Hugh Hetherington Hearing Aid Museum

The Hearing Aid Museum

Hearing Aids of all types—Ear Trumpets, Carbon Hearing Aids, Vacuum Tube Hearing Aids, Transistor Hearing Aids, Body Hearing Aids, Eyeglass Hearing Aids and much more!

Home Enter the Museum About Us Contact Us

FREE Subscription to:
Hearing Loss Help
The premier e-zine for people with hearing loss

Your email address
will never be
rented, traded or sold!

Your First Name:
Your E-mail:
Search this site:

 Results per
 page

 all words
 any words


Click on the "General Information" button (top button above) for an overview and general information on this category of hearing aid.

 

Hearing Aid Batteries

Eveready E400 Mercury Hearing Aid Battery

The Eveready E400 1.4 volt mercury battery was manufactured by the Union Carbide Corp of New York, NY for behind-the-ear hearing aids from the mid 1950s? until hearing aids standardized on 4 basic sizes of batteries around 1980 or so.

This battery weighed less than 1 g and measured 0.455" in diameter by 0.135" high. It had a capacity of 75 mAh.

Click picture for larger view

 

Back Next

 
Top view of the Eveready E400 mercury battery showing the positive terminal.

Patent number 2542575 was filed in 1946 and issued in 1951.
 

 

Click picture for larger view

 
Bottom view of the Eveready E400 mercury battery. The bottom and sides comprised the negative terminal of the battery.


 

Click picture for larger view

 
The Eveready E400 mercury batteries were sold in blister paks of 6 batteries each.

It seems the E400 battery was a newer version of the older E400E battery, but they appear to be identical from the outside and in function.

These batteries probably date from the 1970s.
 

Click picture for larger view

 

Bottom view of the Eveready E400 mercury battery pak.


 

 


 

Click picture for larger view

 

(If a larger picture doesn't appear, you may have to turn your pop-up blocker off)