You are viewing this forums as a guest which limits you to read only status.
Only registered members may post stories, questions, classifieds, reply to other posts, contact other members using built in messaging and use many other features found on these forums.
Why not register and join us today? It's free! (We don't share your email addresses with anyone.) We keep email addresses of our users to protect them and others from bad people posting things they shouldn't.
This is worth reading re NiCd & NiMh batteries although it makes no ref to the later/newer LSD type NiMh batteries sutch as Eneloop.
http://www.ebay.com/gds/Ni-Cd-vs-Ni-MH-Batteries-/10000000177628842/g.html
Here is a bit of info re Eneloop LSD NiMH batteries.
Low self-discharge cells.
Eneloop low self-discharge NiMH batteriesA new type of nickel
No worries Joe...just send it a long when you can and I will take a look...
I am going to buy a DJI Phantom 2 in a couple of days....it has a v2 naza and a gimble for a Hero camera...should be nice.
I have learnt my lesson and I promise not to overload you or anyone else in an attempt to explain something. I'm getting off this forum.
I can only go by what a person writes. I can't see what actually is on the person's mind when writing it.
As an ex RAAF instrument Techo trained on 14 different military aircraft types from fighter jets to transport and multi engined comercial turbo jets and helo's cross trained Radio and Electrical on three of them plus being a qualified radio and television servicman, an Amateur Astronomer and a fully qualified gemmologist. I think it will take a hell of a lot more than batteries to Overload my brain.
Just because you can't get through to one bloke is no reason to leave the forum. Everybody here has something to contribute no matter what their IQ. We cannot all be like Steven hawkins.
e-Bay seller rdana has done a comprehensive test on AA, AAA, C and D cells. The results are tabulated and list capacities along with internal resistance.
The testing was done with a battery analyzer as the control as slightly different testing parameters are employed by the five charger/testers. The test was done on 19 different AA batteries including those talked about in this thread. Lesser quantities of AAA, C and D cells were tested.
The testing confirmed much of my own knowledge which did not coincide with many statements in this thread. But not wanting to start a controversy...I will let you read about the test and check out the results for yourself. AMAZING to say the least.
I am not trying to promote any one battery or charger, but the below link will get you to one of the many pages that the report is on. You will have to scroll down past the info on the charger to read of the test and see the results. Cut and paste or type it into your browser if it does not open the e-Bay page.
Interesting test that seems to confirm that the majority of the batteries tested conform to manufacturers specs.
I have tested a wide range of batteries during the past 3 years using an ESR meter (Equivilant Series Resistance ) meter in an attempt to locate faulty batteries in a pack but came to the conclusion that the ESR meter does not give an accurate indiation of a batteries actual capacity because dead cells and full cells gave very similar ESR readings. The terminal voltage indicated when a battery was dead but gave no indication at all as to the batteries ability to accept and hold a charge. Like the charger in the Ebay listing , my charger determins if the battery/batteries are accepting a charge and cuts off the charge cycle when a faulty battery is detected..
I was hoping that the ESR meter would indicate if a battery was no longer able to be recharged prior to placing the batteries in the charger and so I would not waste time trying to charge dud batteries but that was not the case. I thought that the internal resistance of a good fully charged cell may be significantly different to that of a dead or faulty cell. On the other hand it does not take my charger very long to detect a faulty battery..
I later carried out similar testing using a Battery Impedance Meter but came up with inconclusive results.
The Impedance meter did indicate which batteries had the lowest internal impedance but gave no indication of the batteries ability to accept a recharge.
My edit time timed out on the above post so here is a bit more.
So I guess you can say that a battery that has an internal resistance significantly higher than that of a fully charged cell of the same type and capacity MAY be a faulty cell or that it may simply be a bit flat.
Measuring the cell terminal voltage will tell you if the battery is flat or fully charged. BUT! It is possible for a cell to be incapable of delivering current while still displaying a full terminal voltage (No load voltage)..
If you have recharged your battery pack then if possible check each battery for full terminal voltage with a voltmeter. If any are lower than full voltage after a normal charge cycle then toss them out because they are likely on the road to failure and could cause your metal detector to not function correctly, plus they will prevent the rest of the batteries in the pack from taking on a full charge or could possibly cause the pack to overheat during recharge and this will shorten the life of the batteries.
After several hours of looking at YouTube, reading different reports and trying to sort out the good/bad/BS informationI am going to:
1) sort my AA rechargeable, keep and use them in sets where the cells are within 10% of each other
2) not use any rechargeable cell in a detector when it falls below 30% of its rated capacity
3) only by cells from a reputable source, at a fair price. There are many reports of cells selling at an unbelievable low price that are indeed labeled with much higher than their actual capacity
4) stay with the standard (non-LSD) cells for now, I use my rechargeable within a week or two of charging them before they need to be recharged again.
I now believe the most reliable measurement of the usefulness of a rechargeable NiHM is its CAPACITY. Each of the listed charger/tester (in my previous post) register capacity. The actual results compared to another charger/tester is immaterial as the cells will be grouped in relation to each of the other cells using one test system. The shown charger/tester probably are not calibrated and as with all electronic devices they have a tolerance and show test results within the units design rated tolerance (if you could find them).
Thanks to all that have chimed in on this topic.
BTW a battery is made from two or more cells. AAA, AA, C D are cells. The rectangular 9V "transistor radio battery" is indeed a battery made up of 6 cells. That is why a rechargeable rechargeable 9V battery only charges to 7.2 volts and will not power some devices. There are a few newer rechargeable 9V batteries with 7 cells and charge to 8.2 but have a lower capacity than the 7.2V battery. The reason for this is that the capacity of a cell is constrained to just how much of the cell's chemicals and parts can be fit into the industry maximun can size for any given cell. That is why I have not seen a cell with test results above about 2650mAH even though they are labeled higher. I have seen some new cheap 3000mAH AA cells test below 700mAH.
Some great advice Waterwalker.
Yes I would like to thank all of those that contributed to this post. Some of you put a lot of time and effort into this. With over 2500 hits on this post I am sure lots of others have also got advice and tips. I know this is one post that is going to save me some money and save a bit of the environment too.
Thanks again
Joe
I saw a solar panel on the tv and it was very thin....you could role it up like paper and it had high output ....
They said the material was about ready to be released to manufactures ....
I think I will mount one of those on one of my detectors to charge the battery while detecting...
I don't know if it will match or exceed the draw of the detector but I'm sure it will extend the runtime of the battery.
If it exceeds the detectors needs...then you could power other things like...charging the on board batteries to run...
A 'Hot Grip' for the cold weather hunter.....a speaker amplifier.....a GoPro camera for filming ....YOU ! Etc.
It would be the heart of your detectors very own 'Power Plant'.....
Hello i don t understand all what you said joemac... you think it can be a difference power pulse between the stock accus (2400) and the 3000 or just win a few hours more ? stock rechargeble batteries can run 2 days with 4 hours each , after have to charge its enauf ...
I buy standard batteries (1800 i remeber..) just one day detecting 7 hours after...in the trasch
I think you missed the point of this discussion. Rechargeable's save you shit loads of money in the long run and saves the environment from all the discharged batteries that you put in the trash. Also saves you carrying shit loads of batteries on long excursions. There is plenty of info in this thread. Hope that clears up any questions. All the best.
Hi all- I just thought I'd mention that Panasonic bought Sanyo last year. The latest generation of the Eneloops are marketed as Panasonic Eneloop. The newest ones (generation 4) offer 2100 recharge cycles. The generation 3 ones were rated 1800 cycles, and generation 2 were rated 1500 cycles. The capacity remains unchanged; 2000mAH, minimum 1900.
There's more technical info at:
http://en.wikipedia.org/wiki/Eneloop
