Rechargable Batteries AA - what to look for?

[bigdazzler]

2. Which is the better option... the C900 (4 at a time) or the C801D ( 8 at a time)? Would prefer to do 8 at once, but if the C900 gives a better result then that's the way I would go.

I have the 801D, and I only use eneloops. It is a fantastic combo, you wont be disappointed mate. Its very handy to be able to charge 8 at once.

[Kym]

I can only speak to the C9000 - the cells get warm but not hot. It works very very well.
It is also a manager meaning is does full discharge recycles etc. measuring capacity as it goes.

Can you vary the rate of the Rezap? Sounds like you are charging at a too high rate.

[rogklee]

I got the C900 I think and the powerex batts from jeff. Pretty cool stuff. Met Jeff as well and his a good guy, he'll look after you and teach you how to use the batts too.

3 Thumbs up!!!!

[Natsky]

Can you vary the rate of the Rezap? Sounds like you are charging at a too high rate.

No manual settings on the Rezap Kym. I suspect it is overcharging at times and yet at others it doesn't give a full charge and I am changing batteries 50 flashes into a wedding...frustrating. Have checked the instructions repeatedly and am definitely using correctly. Been using Energizer 2700 and have cooked/killed about 6 now.

The C9000 seems complex compared to the 801D and the convenience of charging 8 at a time is appealing. I generally take at least a dozen batteries to a wedding so overnight/trickle charging 4 at a time takes a while. Definitely going to purchase one of the chargers, but still not sure which...just want to make the right decision and get on with it.

[Scotty72]

I am about to be the next sevaas customer

Only, I too am wondering about the C900 or the C801D choice.

Is the way the c900 handles batteries that much better than the 8x charger?

Decisions, decisions... any advice?

[jibbonpoint]

once upon a time, it was recommended that re-chargable batteries be completely discharged before recharging. It was a "memory" issue. I still do the same with my K10D; carrying a spare.

Is this still the case?

[bigdazzler]

once upon a time, it was recommended that re-chargable batteries be completely discharged before recharging. It was a "memory" issue. I still do the same with my K10D; carrying a spare.

Is this still the case?

the Maha 801D has a "Deep Conditioning mode". It will run them dead, recondition, and recharge. Takes up to 24 hours so I wouldnt do it when youre in a hurry. I normally deep discharge about once in every 4 or 5 charges. I assume the C900 has this too ?? Dunno.

[etherial]

That was a significant issue with with the old NiCd batteries. It isn't really an issue with the newer NiMh batteries, although giving them a full drain and recharge every now and then is still a good idea.

[Kym]

The C9000 does a deep discharge cycle. Its called 'Break-in' in the manual.

NiCd have a memory problem. NiMH don't. The purpose of deep cycles is to improve or maintain capacity.

[DavidB]

For me, must-haves in chargers include:

• The use of separate charging circuits for each battery. Otherwise a failing cell can cause others to be overcharged, etc.
• Temperature sensing to avoid overheating the cells (ideally individually).
• Control over the charging current (different battery models have different needs). Ideally this is a per-battery control.

Another charger option (one that I use) is the LaCrosse BC-900. Not available from any Aussie retailers though. Otherwise the Maha chargers are good. The MH-C9000 is the bees knees, although at first glance all the options can be a bit daunting.
The BC-900 is smaller than the MH-C9000 (room and weight in my checked bag is always an issue on trips).

As far as batteries go, the Eneloops are great. But as well as Eneloops I use the Powerex Imedions (also available from Servaas). The have essentially the same characteristics, and are rated as 2100 mAh. I also have a bunch of older "2400 mAh" plain NiMH cells, but they're gradually being phased out of my collection. One of my "plain" NiMH cells died during my recent Norwegian trip. The charger showed me it wasn't taking a charge, and didn't damage any of the other cells being charged at the same time.

[coolie21]

I went with the Maha C9000 deal from Servaas the other day before reading this thread, looks like I made a good choice. Came with 4 Powerex 2700 and 4 Imedions. Great deal.

That charger is like nothing I have ever seen before, I've had the powerexes on the 'break in setting' and it is still working through them after 2 days

[Loopy]

Had problems with standard batteries with my Pentax k-x. Switched to Eneloop and they are great. Highly recommended.

[RamblinR]

I use Sony Eneloops and Sony CycleEnergy. Both are very good and retain their charge.

I also use an Enecharger which holds 8 batteries and charges cells individually.

I carry mine in the following personally designed and made Battery Wallet. It's great as it holds up to 16 batteries or just fill one side for eight. Used batteries get put back in bum up so I know which are charged and which empty.

[peterb666]

I have posted before that I prefer use either Sanyo Eneloop or Varta Ready2Use these days. You can leave these lying around for months and they are still fully charged. I have used quite a few of the older style NiMH batteries in capacities ranging from 1800 to 2800 mA/h rating over a number of years and found the higher the rating the shorter the battery life (in number of recharges). Higher capacity, conventional NiMH batteries also have a quicker self-discharge rate.

As NiMH does not need to be fully discharged and are quite happy with top-up charges; deep conditioning charges just shorten the life of the battery. Deep conditioning should only be used with NiCad batteries which simply are not worth the time of day these days.

[kptn82]

http://photography-on-the.net/forum/...d.php?t=677074

This link might be of interest to you all, I had the same questions and found this test results! Awesome reading actually.

[PROtog]

I have posted before that I prefer use either Sanyo Eneloop or Varta Ready2Use these days. You can leave these lying around for months and they are still fully charged. I have used quite a few of the older style NiMH batteries in capacities ranging from 1800 to 2800 mA/h rating over a number of years and found the higher the rating the shorter the battery life (in number of recharges). Higher capacity, conventional NiMH batteries also have a quicker self-discharge rate.

Agreed, for the average photographer, Low Self Discharge batteries are the way to go. For the wedding, press, or events photographers, a high quality NiMH AA battery will outperform any low discharge battery for flash refresh rate, and number of shots per set of battery.

As NiMH does not need to be fully discharged and are quite happy with top-up charges; deep conditioning charges just shorten the life of the battery.

I agree, so long as the batteries are being used on a weekly basis. Batteries are happiest when they are busy. If you have a set of (normal NiMH or Low Self Discharge NiMH) batteries that have not been used for 1 or 2 months, putting them through a discharge and charge cycle just before you use them will give them some exercise and 'wake them up' and you will get better performance from them.

[Colinc1]

Another order on its way to servaas for a charger & batteries

Cheers
Colin

[peterb666]

If you have a set of (normal NiMH or Low Self Discharge NiMH) batteries that have not been used for 1 or 2 months, putting them through a discharge and charge cycle just before you use them ...

After 1 or 2 months, your normal NiMH are going to be as dead as a doornail and have to be recharged. No need to put them through a discharge at all.

After 1 or 2 months, the low discharge version will have essentially the same charge as when you put them away. After about a year, they will still retain around 85% of their charge (even more if you left them half-charged which I have read gives the longest retention - beats me why).

A battery creates power using the electrical potential differences between different materials and an electrolyte allows that potential to flow.

A rechargable battery allows for that process to be reversed but there is a limit as it cannot be 100% efficient. Each time you submit a battery that does not have a memory effect to an unnecessary discarge and recharge, you are reducing the number of remaining cycles left in the battery.

I am sure you know this but others may not.

[PROtog]

After 1 or 2 months, your normal NiMH are going to be as dead as a doornail and have to be recharged. No need to put them through a discharge at all.

That is certainly true of many brands of NiMH battery, but not all. I have measured the discharge rate of a two year old set of Powerex 2700mAh AA after 60 days in my office drawer (not a controlled lab environment) and the discharge figures were as follows:



Afer 60 days the batteries were discharged @500mA to see the remaining charge. They were then charged at 1000mA to measure the full capacity. This test shows that the Powerex 2700's have very good self discharge characteristics for a non LSD battery. These batteries had been cycled about 20 times in my Pentax K100D, and considering the age of the batteries, their capacity has not degraded significantly over time.

After 1 or 2 months, the low discharge version will have essentially the same charge as when you put them away. After about a year, they will still retain around 85% of their charge

Yes, for most users LSD batteries are better.

[johndom]

I have some newer energizers and charge them up on an old school basic charger, as well as a stack of DSE batteries that are nearly 2 years old and gradually getting moved to the remote control and kids toys pile. The energizers are 6 months old and just starting to show signs of age. Still, I have been getting a lot of work out of them in that time, packshots and events, both being quite flash intensive. They have paid for themselves many times over that period.
Are there any other battery/charger site or shops? I remember a good battery shop down at Birkenhead point/Sydney, but I am not sure if they do much AA.