Sanyo 2500mAh battery discharge issue

[Lenscapes]

I also got these Sanyo 2500mah battries also with the same problem.
I did a simple test charging on 2pcs of Sanyo 2500mah battries together with 2pc of 2500mah Konnoc batteries. After 1 week plus the voltage on the Konnoc measured > 1.3xV but the Sanyo on was about 1.2xV only. Seems like Sanyo batteries losing its juices quite fast.

Just wonder can they be exchange for a new one?

hmm.. i thot the correct way is to measure the ampere, not the voltage? correct me if i am wrong. :dunno:

 

[xtechchu]

hmm.. i thot the correct way is to measure the ampere, not the voltage? correct me if i am wrong. :dunno:

ampere is current measurement. i.e. is like how much juice (or amount of ) the appliances it going to suck up from the batteries. The lesser the better, which mean it, can be use for a long period of time. Normally, this will depend of the design of the appliances.

For a fully charge NiMn batteries it should measure somewhere 1.47V, once it used up (or prolong un-use) then the batteries power will use up or diminish below 1.20V, then is time to charge again.

However, though 1.20V is it still got some juice which still can use for another appliances such as portable radio especially the analog one, children toys, touch light. This is a good time to drain off the remain juice in the batteries before another fresh charge begin.

BTW, mine Sany batch number is # 04-12 0A

 

[frenzatwork]

haiz...if i had read this thread earlier, then wouldn't have bought another 8 pcs of 2500 from EG after they adviced to pass them the "problematic" 2500 to check...anyone tried contacting Sanyo Singapore about this?

 

[di0nysus]

I've posted this to sanyo singapore

Dear Sanyo,

I've been faithfully using Sanyo 2100s and 2300s AA for my cameras. Sanyo AAs are the choice for most photographers at the moment. We continued to support sanyo when the 2500s came out. However, there is a issue with quick discharge. After charging (using sanyo chargers), one must use the batteries almost immediately, else after leaving fully charged 2500s alone for a few days to a week, all the charge is gone!

The batch number that we've discovered so far includes
05-01-0A
04-12-0A

We're hoping for an exchange with good batteries or a refund. We do hope to continue to support Sanyo in future.

regards
***
9******

 

[xtechchu]

I've posted this to sanyo singapore

Any reply from Sanyo yet?

 

[melvin]

before using the batts, do you guys just charge it up normally, or fully discharge-then-charge?

for me, i'm a bit kiasu, i go for the latter. just wondering if its ok to do the former.

I also the kiasu type n i always make sure they are really flat then i recharge to my knowledge it is best to fully discharge batts before that will prolong the batt life! (all sorts of rechargeable batt is the same my handphone batt also same recently one of my hp batt last me 3yrs n still ok... but of coz the life span shorter each charge last me about 2 days)

If charge before it is fully discharge your batt life span will be cut short very fast!

Just speaking from experience with rechargeable batt!

 

[melvin]

eh? never had any problems for me. after a full charge, takes abt a wk of non-use for it to totally discharge.

normally, i marked my batts with dots to indicate grouping. so, i charge the batts with the same dot markings together. something my old encik taught us blur recruits abt preventing our uniforms from being 2 different colours - marking the pants and no4 so we wear and wash them together. so far, the 'logic' works for my batts too. :bsmilie:

Same here me got no problem with my Sanyo 2500mAh batt. So far so good into the 6th months, I always refresh them before each charge!:bsmilie:

 

[AhV]

I am posting here again ...man..some of you are just lucky souls....my 2500 batts died on me again..completely out of juice....bought 8 pcs together with my MAHA charger from EG

My batch number is 04-09-SH if it means anything to us ??? ........bought them when they were launched ...so these must be the first few batches .....this discharge issue is getting on my nerves :sweat:


Arrgggg.....hhhh ..I hope SANYO will respond to our feedback and offer some solution/ replacement. I am sure EG is not aware of such problem.

 

[xooler]

This is very common of Sanyo batteries. I got a few 2100mh also like that. My brothers also got 2300 or something, also like that. His friends too.

In the end, what did we get? Sony and GP. Yes, GP....

And, a shop keeper friend tells me that his customer also complain abut Sanyo then then he switch to GP. Now his stock is moving.

 

[Michael68]

Just wondering if it has anything to do with the charger? I have both the Sanyo and the Maha charger and when I switched to Sanyo charger, I solved the problem...

 

[Madman]

I slow charge my batteries and they discharge after 1 week for me too...

You guys on quick charge or slow charge? Would it make any difference?

 

[melvin]

I slow charge my batteries and they discharge after 1 week for me too...

You guys on quick charge or slow charge? Would it make any difference?

:dunno: DUnno if there is any diff. For me i play it safe normal charge.

 

[Michael68]

The quick charge shortens the life span of your batteries. This is well documented in various websites on batteries. If you do not really have any urgency and can plan your photo shoot in advance, do the normal charge. Quick charge usually applies when you are overseas and it is critical to get your batteries recharged for the next day's tour etc.

 

[AhV]

Just wondering if it has anything to do with the charger? I have both the Sanyo and the Maha charger and when I switched to Sanyo charger, I solved the problem...

MAHA is one of the best charger available in the market .... it's worrying to know you solved the discharge issue by just using a SANYO charger :sweat: What can a SANYO charger do that a MAHA cant ?

I believe most of us would own one ....*haii* my 2500s came without a charger

 

[eow]

same prob here bros
my freshly charged 2500ma batt last only two days of random usage taken less than 50 shots in total :angry:
04
11
ul

 

[Michael68]

MAHA is one of the best charger available in the market .... it's worrying to know you solved the discharge issue by just using a SANYO charger :sweat: What can a SANYO charger do that a MAHA cant ?

I believe most of us would own one ....*haii* my 2500s came without a charger

I owned the newer version that has a trickle mode but without refresh function. The Sanyo charger is the one with the refresh function. Funny thing is.....batteries charged by the Maha do not seem to last as long as that by the Sanyo....and this includes other brand batteries such as Sony, Panasonic etc....

Well, I guess there must be some explanation for this.....

 

[Scaglietti]

I am curious when the batteries are fresh from the packing or after a number of cycles. Some NiMH may not achieve the full performance during the initial few cycles.

 

[xtechchu]

My batch number is 04-09-SH if it means anything to us ??? ........

My best guess is 04-09 (04 - year 2004, 09 - Work Week #09).

Thus, it is likely those 2500mah Sanyo batteries produced during these period could have some process issues.

 

[Denosha]

My affected batts are from the 04-10 batch... Really does look like some sort of common problem with the batts produced during this period. =^(

 

[ultrasmurf]

The quick charge shortens the life span of your batteries. This is well documented in various websites on batteries. If you do not really have any urgency and can plan your photo shoot in advance, do the normal charge. Quick charge usually applies when you are overseas and it is critical to get your batteries recharged for the next day's tour etc.

Just to chip in a little bit, in general this is true, but for ni-mh a fast charge is preferred for a better end of charge detection. NiMH has a much smaller -deltaV compared to NiCad. Doing fast charge increases this deltaV to a more detectable level. Failing to detect this result in dependency on thermal detection and timer, both of which often result in overcharging which kill battery faster than doing a repeated fast charge.