Unfussy USB powered charger for old Ni-MH cells... XTAR VC4 series?


Newly Enlightened
Jan 3, 2010
Yorkshire, UK
I've got a number of fairly old but usable GP AAA NiMH cells which my Maha C9000 charger doesn't like. It detects high internal resistance and refuses to charge them.

Yet the same cells will charge perfectly well in an old "dumb" charger, and they will work just fine once charged (they're used in my daughter's Lego Power Functions stuff). Sadly that old charger is horrendously slow at about 85mA!

From what I gather the C9000 is notoriously sensitive to this, especially where AAA cells are concerned. So I was pondering a new charger, something that'll charge 4x NiMH cells at a reasonable rate (say 500 to 1000mA), and ideally one that runs from a USB phone/tablet charger, rather than a dedicated wall wart.

There's a variety of XTAR VC4 series chargers on Amazon for around £20 that look like they'll do the job, e.g. VC4, VC4H etc. But before I spend money on one, can anyone advise as to whether these XTAR chargers will tolerate less than perfect cells? Or are they similarly fussy to the C9000?

(Note: I don't want to throw money at new cells as I'd need loads of them, and they'd likely suffer the same fate... That Lego setup requires 6x cells for each of the motor battery boxes, plus another 3 for each of the wireless controllers. Daughter has 2 of each, and tends to run the batteries until they're truly dead, then leave it several days before asking me to recharge the batteries!)