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scottyja
11-12-2004, 10:23 AM
Hoping someone out there can clue me in - a couple of months ago I bought a DigiPower one-hour charger w/ 4 2100 mAh batteries. Being new to digicams and rechargeable batteries, I didn't know you had to charge them first. So I plugged them into my Canon A95, and obviously I didn't get too far. However, even after realizing my mistake and recharging them, I was getting 10 - 15 pictures max (w/ flash). Very frustrating... I've recharged them 5 or 6 times.

So I'm wondering, were the batteries duds? Did I mess up the batteries' memory by not charging first? Is the charger bad? Or (let's hope not) is it a camera problem? :(

Have any of you had any similar problems? What was the cause/solution?

For the time being, I bought some Duracell 2300 mAh batteries (from walmart, Rhys) and charge them in my DigiPower charger. I haven't noticed any problems yet, but have only taken about 10 pictures with them so far; to early to tell if it's the charger or camera, I guess.

I would love to hear your insights. Thanks!

Terracotta
11-12-2004, 10:54 AM
If you got the cheapest AA cells you could I bet they're low-voltage only-good-for-torches stuff and your dura's will walk all over them. Typically I use Vanson batterys, they're cheap and while not up with the best for life but they've got a lot better price/life ratio than the likes of Duracell (oft over 2x the price) or Mica's own brand (10% less but 50% the life). Battery prices are kinda like PC prices, you pay a shed load for the top spec thing, step back a step or two and for half the the price you get the 85% of the performance, go for rock bottom and you get an unreliable item which doesn't live up to the spec.

Why do cheaper non-rechargeables work every time? Cause non-rechargeables start at about 1.65v (Duracell/Eveready etc. ultra-long life battery's start here), dropping to about 1.4v for the cheap in-store branded items. Rechargeables start at 1.3v with the likes of Duracell, most of the cheaper branded 'bulk sell' (Vanson spring to mind) are about 1.2v and your cheap in-store brands can start at 1.0v!

Also the quicker your charger the lower the 'fully charged' state is, most long-charge just keep on pushing current in until you turn them off. Quick chargers (6~10 hours) push current in until they get 0 delta-V across the battery, typically this happens at about 90% full charge, and then go into trickle charge mode (same speed as slow chargers) to finish them off. Rapid chargers do the same as quick but a rule of thumb is 75~80% charged until they go into trickle charge mode.

ReF
11-14-2004, 05:22 AM
I've heard that you are supposed to fully the batteries before using them for the first time, otherwise it is bad for the battery. Not sure if this is true, but if it is, then not charging your battery at all and then using them could destroy them. Again, not sure of it.

Terracotta, do you know if it makes any difference if you charge the same batteries on two completely different chargers? I have two sets of 4 batteries, and two chargers, one is slow and one is super-slow. sometimes I charge both sets at the same time if I'm on vacation. The older set came with the super-slow charger, which I used for a year. the first time I charged the older set on the newer, slightly faster charger, it got really hot, even though it charges at a trickle. after that it's been fine, but I charge my newer batteries only with the faster charger. is this a routine I can give up? can I just charge whichever set on whichever charger I want?

by the way, if you are thinking that I should just get a better charger that can charge them both fast, well, I've thought of that too. but I got my Maxell brand charger and 4 1850mah batteries for a killer deal of $12, and they last a very good amount of time. as for the super slow charger, it came with 4 decent 1800mah batteries which I also got for $12 at a time when I didn't know any better. considering the maxells last more than a day (around 250-275 photos plus reviewing) and the older batteries give out right when the day is done, I just can't justify spending $40-$50 on one set of Maha batteries and a charger.

Terracotta
11-14-2004, 06:57 AM
I've heard that you are supposed to fully the batteries before using them for the first time, otherwise it is bad for the battery. Not sure if this is true, but if it is, then not charging your battery at all and then using them could destroy them. Again, not sure of it.
I think this has much more to do with NiCd than NiMH, I wrote off a set of NiCd's cause I didn't charge them before use and they were 40% depleted (this is for a bike light meant I could only just make it to work, 35min ride, before they needed recharging, the second set of the same capacity easily last 100 min). I've not seen this in NiMH. However if you totally deplete a battery you de-ionise it and it's dead for good doesn't matter if it's NiCd, NiMH, Li-Ion etc.



Terracotta, do you know if it makes any difference if you charge the same batteries on two completely different chargers? I have two sets of 4 batteries, and two chargers, one is slow and one is super-slow. sometimes I charge both sets at the same time if I'm on vacation. The older set came with the super-slow charger, which I used for a year. the first time I charged the older set on the newer, slightly faster charger, it got really hot, even though it charges at a trickle. after that it's been fine, but I charge my newer batteries only with the faster charger. is this a routine I can give up? can I just charge whichever set on whichever charger I want?
The older the battery the more resistant to charging it is, if you try to charge it hard it'll heat up, all do but older ones lose more energy to heat than newer (it's an age thing). Define slow & super-slow, a normal (trickle) charger is something like 24hours, quick is 6~12hours, rapid is sub-4 hours. If batterys are getting hot, not warm but hot, when charged with a quick charger then they're getting towards the end of their life.

Rapid charging with NiCd batterys is a total no-no, simply they can't take it (which is why 6~12 hours is a quick charger, they're right on the safe charging limit of NiCd), however with NiMH all should be fine with any charger up to 2 hours, some of the cheaper types don't like ultra-rapid charging (12 min to 75% type chargers, and from what I understand these fellas kill off NiMH in double quick time anyway) & get a little to hot during a 1 hour charging cycle. I'd say that as long as you're using NiMH & you've got no sub-2 hour chargers you shouldn't worry about the batterys but if they start to get hot, rather than warm, I'd consider throwing them in the bin.



by the way, if you are thinking that I should just get a better charger that can charge them both fast, well, I've thought of that too. but I got my Maxell brand charger and 4 1850mah batteries for a killer deal of $12, and they last a very good amount of time. as for the super slow charger, it came with 4 decent 1800mah batteries which I also got for $12 at a time when I didn't know any better. considering the maxells last more than a day (around 250-275 photos plus reviewing) and the older batteries give out right when the day is done, I just can't justify spending $40-$50 on one set of Maha batteries and a charger.
I personally use two expensive and very good chargers, a Uniros 5 banks of 4 cell 7/10 hour charger (this has a lot of bells and whistles & is one of the few chargers that officially support 24/7 charging) & a Vanson 2 banks of 4 cell 2 hour with finished alarm (it's a great charger if you want a fast turn-around, if you've used a Minolta S414 you'll know why I got this charger). But then again I don't mind spending a lot of money if the item I'm buying is worth it.

ReF
11-15-2004, 12:03 AM
My "slow" charger takes about 9 hours to charge 1800 batteries and the "super-slow" charger takes about 22 hours. The one year old no-name batteries only got hot that one time. It does feel like they have about 20-25% less capacity than the new ones. Is it supposed to loose that much capacity within 1 year? I read somewhere that performance isn't supposed to drop dramatically until about 2-3 years after the first charging, but then again maybe 25% doesn't count as a much of a performance drop?

Terracotta
11-15-2004, 02:53 AM
So you've got a normal & quick charger (yes I know they take a long time). Well, the older no-name could never had as much ability as the second set to start with. Though batteries do deteriorate over time the thing that does the damage is charging cycles (a cycle is an effective depletion and recharge of the battery, that is to day using 25% of the batteries capacity then recharge to 100% 4 times is one cycle), you should find that most have x thousand charge cycles, this is the ave number of cycles you can put the batteries through before they drop to 80% capacity, independent of time.

Rhys
11-15-2004, 10:08 AM
So you've got a normal & quick charger (yes I know they take a long time). Well, the older no-name could never had as much ability as the second set to start with. Though batteries do deteriorate over time the thing that does the damage is charging cycles (a cycle is an effective depletion and recharge of the battery, that is to day using 25% of the batteries capacity then recharge to 100% 4 times is one cycle), you should find that most have x thousand charge cycles, this is the ave number of cycles you can put the batteries through before they drop to 80% capacity, independent of time.

what about chargers that allegedly recondition the batteries? Are they any good?

Terracotta
11-15-2004, 11:42 AM
what about chargers that allegedly recondition the batteries? Are they any good?
I'd love to know how they'd de-ionise the battery, the discharge/recharging process slowly ionises contents the cells... I've not looked into these as I've never looked into chargers in that much detail, I'll admit to having dismissed them out of had, mainly due to my knowledge of batteries, my guess is they off-set slightly into sine curve into negative side which would help reduce ionisation. But it would only reduce the impact of ionisation not recondition, the only way to de-ionise the contents is replace it.

EDIT: I may have transposed ionisation & de-ionisation, I always get this wrong.. like fusion and fission in starts, I'm always transposing those too.

Rhys
11-15-2004, 12:04 PM
I'd love to know how they'd de-ionise the battery, the discharge/recharging process slowly ionises contents the cells... I've not looked into these as I've never looked into chargers in that much detail, I'll admit to having dismissed them out of had, mainly due to my knowledge of batteries, my guess is they off-set slightly into sine curve into negative side which would help reduce ionisation. But it would only reduce the impact of ionisation not recondition, the only way to de-ionise the contents is replace it.

EDIT: I may have transposed ionisation & de-ionisation, I always get this wrong.. like fusion and fission in starts, I'm always transposing those too.

I wonder whether it's something to do with blasting the battery with an inverted square wave. In other words, reverse-charge in bursts in order to shift the ions back from the cathode to the anode and then to charge normally.

D70FAN
11-15-2004, 12:26 PM
what about chargers that allegedly recondition the batteries? Are they any good?

Rhys, I've had my Maha C204F for about 5 years. I have had to recondition twice (real old 1600mAh GP's) and it did a great job.

As I may have written before, I have had 3 chargers, and the MAHA C204 is the only one that charges to full capacity, regardless of the battery manufacturer. I have had a Panasonic (came with the batteries) and a Radio Shack charger, and niether would charge to full capacity.

Also of all the different NiMH battery brands I've had and used the Panasonics, Powerex, Nexcell, and GP's have done very well. The Lenmars (cheepos) are worth avoiding for many reasons.

I generally order from Thomas Distributing, and have always received good value from their products. Especially the MAHA charges.

Rhys
11-15-2004, 12:48 PM
Rhys, I've had my Maha C204F for about 5 years. I have had to recondition twice (real old 1600mAh GP's) and it did a great job.

As I may have written before, I have had 3 chargers, and the MAHA C204 is the only one that charges to full capacity, regardless of the battery manufacturer. I have had a Panasonic (came with the batteries) and a Radio Shack charger, and niether would charge to full capacity.

Also of all the different NiMH battery brands I've had and used the Panasonics, Powerex, Nexcell, and GP's have done very well. The Lenmars (cheepos) are worth avoiding for many reasons.

I generally order from Thomas Distributing, and have always received good value from their products. Especially the MAHA charges.

I'm not entirely sure who makes my charger. I know it came from Wal-Mart and was advertised at $26 but I was actually charged $16 for it. It's Chinese and bears no maker's name. It came with 4x 2100 NiMh batteries. It has conflicting instructions on the pamphlet that came with it but it does seem to charge my batteries. I couldn't find a maha charger anywhere in the shops my GF likes to use (Target, Wal-Mart, Best Buy, Lane Bryant etc or in the local mall.) Any ideas on this one? It has a green LED that tells me when the batteries are charged. It has a switch to use for charging 2 or 4 AA/AAA batteries. Some information indicates it's computerised. Some does not.

Terracotta
11-15-2004, 01:37 PM
After reading George's post I've done some reading and it's interesting. These 'reconditioning' chargers DO NOT 'recondition' the batteries, rather they 'reoptimise' their structure and gaining back the ability to fully discharge the battery again. You can even tell the difference between a heavily ionised battery and a less than optimal structured battery, it's the way the battery falls away at the end of a discharge cycle. That is they're not going to rescue my blasted into the ground NiMH from my bike lights which are ionising at a massive rate, but they will restore most of the capacity of the batteries I use for my digital cameras etc. (quicker than doing a full discharge, rest for a week or so, then a full slowish charge).

Now if we could do this with our brains...

EDIT: no idea on your charger Rhys, looks like a typical in-store/unbraded charger

D70FAN
11-15-2004, 08:55 PM
I'm not entirely sure who makes my charger. I know it came from Wal-Mart and was advertised at $26 but I was actually charged $16 for it. It's Chinese and bears no maker's name. It came with 4x 2100 NiMh batteries. It has conflicting instructions on the pamphlet that came with it but it does seem to charge my batteries. I couldn't find a maha charger anywhere in the shops my GF likes to use (Target, Wal-Mart, Best Buy, Lane Bryant etc or in the local mall.) Any ideas on this one? It has a green LED that tells me when the batteries are charged. It has a switch to use for charging 2 or 4 AA/AAA batteries. Some information indicates it's computerised. Some does not.

The MAHA is carried by Thomas Distributing:

http://nimhbattery.com/batteries.htm

scottyja
11-19-2004, 12:09 PM
Quick chargers (6~10 hours) push current in until they get 0 delta-V across the battery, typically this happens at about 90% full charge, and then go into trickle charge mode (same speed as slow chargers) to finish them off. Rapid chargers do the same as quick but a rule of thumb is 75~80% charged until they go into trickle charge mode.

Is is safe, then, to leave my one-hour charger charging batteries all night, or will harm the batteries in any way? Sometimes that's the most convenient time to charge them, but I usual talk myself out of it and end up babysitting the charger for an hour, and then remove the batteries.

Thanks for all the great info!