Continue to Site

Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

2cell NiMH Battery Charger

Status
Not open for further replies.

ah_mash

New Member
hi folks
this is my first thread here but i know i'll get what i need.
first, i have to admit that i know nothing about circuit designing (i'm a doctor!), but i'm pretty good at just building them.
now here's my thing:
i got four Sony NiMH 4300mAh batteries and was intending to use my charger to charge them (it came with four 2100mAh NiMH batteries), BUT... it couldn't handle them: it read as fully charged but when i put'em in my camera it reads as empty.
so now what i need is a circuit diagram for a smart charger that can charge these batteries (4300mAh) in ca. 4 hours, 2 cells at a time. i could use a standard AC 500mA adapter, but what i exactly need is some modification to stop charging when (really) fully charged (make it smart :)).
PS i'm in Egypt and some of the components in the USA may not be available, so whenever possible, please choose common components.
Thank you for the concern and the thoughts.
Ahmed M.Mashhour
 
what's "counterfit"? i didn't find'em online but they look REALLY original.
however, is there a way to achieve my need?
thank you for the support, blueroomelectronics.
 
There are many fake Sony AA and they look real. Check the Sony site to see what AA NiMH they sell. Last year 2800 was about as big as they came.
 
:( please :( , make my adapter smart, will that help? i need to decide whether i need other batteries or another charger.
thanx
 
:(please :( , make my adapter smart, will this do any help?... i need to decide whether i need to get other batteries or another charger
thanx
 
It is critical that you know the chemistry of your batteries. If your NiMH smart charger could not put any charge into them, perhaps they are not NiMH after all. Are you sure?

Anyway, one relatively simple charger can be built using the Maxim MAX712. The data sheet provides a sample circuit. There are other links on the web with this IC, try google. Note that the MAX712 and MAX713 are closely related so search for either. Like the data sheet says, this chip is only for NiMH or NiCAD.
 
Last edited:
I'm with blueroomelectronics here, the highest capacity you can get AA cells in is 2800mAh. If they're really 4300mAh then they must be C cells. If they'e the same size as AA cells but have 4300mAh printed on them or the packaging then they are counterfeit.
 
ok then, so there's no hope.
thank you every one for the help.
it's been a pleasure to getin contact with you guys.
ciao.
 
I never guess why most people think that charge NiMH , NiCd , or even Li Ion battery are same like car (lead) battery? I was make some chargers for , ICOM handhold radio, for difference YAESU handhold radios, wild Taiwan brands, also for ALINCO 120 , and others. And I never make two identically battery charger. :)
 
I think the counterfeit 4300mAh Ni-MH cells are just old 500mAh Ni-Cad cells.
Or maybe they are old carbon-zinc cells.
 
Status
Not open for further replies.

Latest threads

New Articles From Microcontroller Tips

Back
Top