Sanyo 2500 extra fast selfdischarge

[Ig]

Ihave 8 Sanyo 2500 NiMh batteries which have extremely fast selfdischarge. If used in 1-2 days after charging they work fine, the charging time also looks be right for 2500 batteries, but after a week they can only do about 10 pics on digital camera or ~20 hours in wireless mouse. What can be a problem?
The batteries was bought from eBay, can they be not really made by Sanyo?

 

[NiOOH]

This is a well-known problem with Sanyo (and others) high capacity cells. Nothing much to do, but discard them and get something like Sanyo Eneloop

 

[bfg9000]

Here's the Sanyo 2500 thread. And a related one. Plenty of problems with other 2500 -HR- cells like the Energizers too.

 

[Ig]

Well, I should try search first :duh2:
PS. 04 12 ... At least I have 2 cool plastic cases :rock:

 

[paulr]

Sanyo has been replacing these at no charge, so maybe you can do this through them somehow.

 

[lrp]

I had the same problem and I replaced them with Eneloops and problem solved. I like the Eneloops much more as they last much longer than the NIMH in my devices! I seriously doubt if I ever purchase a NIMH again.

 

[viorel00]

I had the same problem and I replaced them with Eneloops and problem solved. I like the Eneloops much more as they last much longer than the NIMH in my devices! I seriously doubt if I ever purchase a NIMH again.

do you know that Eneloop is NIMH? a low self discharge battery, but NIMH nonetheless.

 

[coppertrail]

Right, they are NiMH, but with some differences from conventional NiMH cells.

I've been very happy with all my Eneloop cells and use them in a variety of devices. They seem to have very consistent voltages and self discharge rates.

 

[VWTim]

I had a total of 9 Sanyo's. 6 still work great, and 3 were horrible.

 

[kathikul]

Well, I should try search first :duh2:
PS. 04 12 ... At least I have 2 cool plastic cases :rock:

If 04 12 is the date stamp on your batteries, they may be from the faulty batches (presume that they are not fake).

I had the same problem after using them exclusively in my wireless optical mouse for a year. At the time, they were at about only 15th cycles (It took so long to reach that number of cycles because, after each recharge, they could power the mouse for longer than a month).

I contacted Sanyo a couple of months ago, and the replacement batteries were sent to me directly from them without any charge. The replacement batteries are still working well (I just finished using the 1st cycle of them after forming/priming).

For more detail, you can check out my previous thread.

 

[rantanplan]

Same experience here ... from 8 Sanyo 2500 mAh 3 were unusable (empty within 24h) after only a few cycles and some months. I bought them originally because I had made very good experiences with my old Sanyos 2100 mAh ...

 

[viorel00]

isn't it amazing how Sanyo can make such crap and at the same time they can also make those jewels called eneloop?

 

[LEDcandle]

Its a batch issue... 2005 mostly... I have 16 pcs of bad batts... but too bad, I already used them and had some wear on the wrappers when stuffing them in a mag mod, so no chance to replace them. I read someone got his batch swapped at the local Sanyo dealer.

I have a 2006 batch which works beautifully... discharges as per normal...

 

[lrp]

I forgot that Eneloops are NIMH!! They last so much longer that it seems they are something else to me....last sooooo much longer!!

 

[Anders]

Hello IG.

I bought Sanyo AA and AAA cells here in sweden a year ago from a web dealer, he sold them by a web auktion.
They where fake ones, Nicd instead of Nimh....
400-500 mAh instead of 2500mAh for AA cells.

This is what i found:
http://forum.lowyat.net/index.php?showtopic=212093&st=0
Compare your cells with the ones in the thread.

Anders

 

[LA OZ]

Fake batteries are almost indistinguishable - beware.

 

[Thujone]

i just decided to check the 1 day discharge on my sanyo 2500. It was sick. ~385mah discharge in 24 hours. Ouch.

 

[Omega Man]

This thread has prompted me to test 2 of my Sanyo 2500 against 2 Energizer 2500s. After 18 hours they're all keeping pretty much the same pace. I'll let it go a week or so and see what they all look like.
For those who got replacements: What exactly did you recieve from Sanyo? Did you have to send in the bad cells?

 

[Mike Iver]

I purchased Titanium nimhs (AA 2600/2700 and AAA 1000) Duracel nimhs (2650), and Energizer (2200) The Titaniums and Energizers work great. The Duracel 2650's are garbage. Right now I am trying to figure out how many are bad. If I use them fresh off the charger they are fine, but some of the cells discharge to less than 1v in less than a week (without use).

 

[Foxx510]

So far, Duracell, Energizer and Sanyo have all replaced or refunded dodgy cells for me. This is in Australia.