I have a number of portable audio players, Walkman and MiniDisc which use the rather convenient “gum-stick” style rechargeable battery.
It becomes less convenient when you want to charge it up.
Sony started to use the thin gum-stick style battery in lieu of the more common LR6, or AA cell to create thinner portable devices.
This is clearly illustrated by these two almost identical cassette Walkman. the bulge on the ‘562 model is there to accommodate the AA size battery. The sleek lines of the ‘662 are possible because it’s gum-stick battery is only a few mm thick. I have Cassette and MiniDisc portables which use these batteries. Not just Sony. I have a Panasonic which takes them as well.
These players can be used with mains adaptors, which also charge the battery. Not always the most convenient way to do things.
Sony made a simple Plug top type charger which accepted a gum-stick. Problem with this was that the original version was for low capacity NiCd batteries. Sony later adopted NiMH technology which requires slightly different charging characteristics. You should use a different charger. If you can find one. Sony are quite vocal about this both on their batteries and on the chargers.
I tracked down this UniRoss charger from a UK supplier. it will do AA, AAA or “Prism”, as it calls gum-sticks. it is equally at home with NiCd and NiMH. I suspect it has intelligent charging circuitry. That’s what I’ve been using for a couple of years.
Now I have this universal USB battery charger. It came to my attention courtesy of the magnificent “Big Clive” on YouTube. If you enjoy your electronics and gadgets explained by a man with a fantastic sexy (I’m told) Scottish accent, who is not adverse to blowing stuff up in the name of science, he’s your man.
For me the killer feature is the magnetic connectors. They are intended to connect to most types of cylindrical batteries. They also work remarkably well for rectangular gum-stick shaped cells. As a bonus I also use it for AA NiMH and larger 4.2V Lithium cells, which it is designed for.
This is a sophisticated smart charger. It works out what sort of battery it is and which way round it is connected, then applies the appropriate charging current for the right time. Because it runs off the USB socket on your Laptop or phone charger and is fully automatic it is extremely convenient. It’s all I use now.
As a parting shot .. When trying to measure the voltage of a battery with a multi-meter, I find that the black test probe works so much better than a Sharpie. I couldn’t figure out why it was so flat. iD10T problems.