A Great Charger, Set Up, & Battery Care

[Critterhunter]

The world of metal detectors lags behind in battery/charger technology versus the electric RC airplane crowd, which seems about 10 years ahead in this area. RC fans, including myself, can be obsessive about taking good care of their batteries and using the latest technology to improve flight time, performance, and battery life, all while lowering the weight of the pack and using chargers which take much of the guess work out of battery care.

Metal detectors, on the other hand, seem to be stuck in the past using heavy packs or at the very least primitive

 

[larzam]

Thanks for the link,i remember this from awhile ago,and it is one of the best informational leads for metal detector batteries i have ever read. Definitely worth going over again,Also - since i quit cig smoking -my E-CIGS use lipo batts also. I truly believe battery technology is advancing faster than most of us can keep up with. sam in ms

 

[Drenthe]

Fantastic! Cant wait to read it. I just came back from a trip that was cut short due to a dead battery that I had recently fully charged!

 

[GONGA]

Thanks Critterhunter for this post ..I have been waiting for someone to give some insight on the matter...I have used lithium ion cells from an old laptop battery that went dead(given to me for free actually)....actually I pulled it apart and there was only one cell dead so I use the cells to make a couple of battery packs and I use my dewalt charger to charge them up I read this on a forum someone had done ...To date I have only ever charged the packs 3 times they just go forever and the detector runs very smoothly with these battery packs...Im glad im not the only one doing this kind of thing .The only thing that has worried me is the excalibur is a 12 volt machine and the these i have made battery packs are around 14 to 14.5 volts...I have never tried the packs on the excal wondering if it will cause damage with the higher voltage ,what is your opinion will it cause damage and what is a safe voltage for the excal....

 

[Critterhunter]

Here is the charger for $23. There are others on theie site with higher wattage but this charger is more than capable for metal detector batteries as well as most RC and other applications. Higher wattage chargers such as the Accucel 8 allow higher charge/discharge rates for faster charge or discharge times. However, the Accucel 6 is the most popular charger in the RC crowd as it

 

[Critterhunter]

First thing to do is set up some of the parameters that will probably never be changed. Turn on the charger. Note that the fan will not run unless you are charging or discharging a battery. Hit the stop key to insure you are in the right menu level and not in one of the submenu charging levels. Hit the

 

[dbsmokey]

how does one print these posts? I would like to print this one and save it. Thanks, Critterhunter, for sharing this.

 

[GONGA]

Thanks for sharing that ...but do any of you guys know the maximum safe voltage that the minelab excalibur excalibur can take..

 

[CSA GHOST]

Excellent post critterhunter!

 

[kered]

My excalibur ll batteries are all over 14v(nimh) when fully charged but i don't know the maximum voltage before damage would ocour.

To print the post you can either copy and paste into a word/notepad doccument the relevent posts you need or right at the top of the page in the explorer/mozila headings under file select print

 

[erikk]

First thing to do is set up some of the parameters that will probably never be changed. Turn on the charger. Note that the fan will not run unless you are charging or discharging a battery. Hit the stop key to insure you are in the right menu level and not in one of the submenu charging levels. Hit the

 

[Critterhunter]

A few minor corrections...

Lipo/LiLo/Life CHK Time should already bet set to 10 min. This is how long the charger will wait to check that it is seeing proper voltage based on the lipo type and cell count. You don

 

[Critterhunter]

Lipo V. Type. This is the individual cell voltage based on lipo type being used. Press Enter to change it and then hit the plus key several times to scroll through and see each available option. They are

 

[Critterhunter]

One other thing I figured I'd cover if it was confusing...To change a setting you hit Enter and it will flash. Then hit + or - to change it, and then Enter again to set it.

 

[Critterhunter]

All good info I guess but after reading that I needed to go and get some aspirin! Reads like programming the space shuttle for take off I am nor too battery savvy or a teckie and all I want two do is charge the excal battery (and others) and hunt. With this set up I can just plug it in and when the green light comes on I am finished. I can also use the charger hooked up to a car battery. Been using this on my exals for a year or so and all is well so far. I am a big fan of the KISS theory I do like your imput just too complicated for me

Erikk, the settings are rather simple once you understand them and they will more than likely never be changed again. This charger gives you control over every aspect of just about every battery type on the market today, and a few of the lipo types it will charge are just now emerging as common on the market. I think one of the lipo modes (life?) can also be used for A123 cells, which are also becomming very popular for various reasons.

The problem with one size fits all plug and charge chargers is they often charge at too high of an amp rate for long life, or charge to slow when you want to speed things up. Not being able to set the delta threshold m/v per cell number can often mean the pack false terminates or doesn't see when the pack is peaked if set to high. Things like capacity numbers also help to monitor pack life. You'll never grow out of this charger.

 

[Critterhunter]

My excalibur ll batteries are all over 14v(nimh) when fully charged but i don't know the maximum voltage before damage would ocour.

To print the post you can either copy and paste into a word/notepad doccument the relevent posts you need or right at the top of the page in the explorer/mozila headings under file select print

Kered, down the road here as this thread gets to charging nimhs and nicads I could use your input on the Excal and Etrac methods you are using such as amp rate to prevent the thermal overload in the Excal packs, connectors, pics of your etrac battery holder, etc. Also need Jim to show his homemade Etrac holder. Do it after I walk people through the nimh/nicad settings and how to charge the stock GT rechargeable pack. This will make a good jumping off point for the Excal/Etrac/Etc. Thanks in advance.

 

[Critterhunter]

As promised, explaining the m/v per cell setting. Nimhs and nicads drop in voltage somer once they reach full charge. A nicad will drop more in voltage than a nimh, thus we've set the nimh m/v setting at 7 m/v per cell and the nicad at 14 m/v per cell. The charger takes that number, times it by the number of cells (it can tell how many there are automaticly for nimhs/nicads), and then expects to see that much of a voltage drop when the pack has peaked. Setting it too low might cause a false termination before the pack is actually charged because the voltage will fluctuate some as the pack chargers, so it must be set higher than these false dips in voltage. Setting it too high might cause the charger to never see that the pack has finished charging.

I have found that 7 for nimhs and 14 for nicads works well no matter how fast or slow I am charging and regardless of pack size. Those settings should work well for you, but as all things in life there are no guarantees. Charging at a very low say 10 hour charge rate (for instance, a 1000ma pack at 100ma or .1 amps would take ten hours) the m/v drop might be less pronounced, so you might consider lowering a nimh m/v setting to 5 and a nicads to 12 or even 10. Charging real fast like say that same pack above at 1 amp would take 1 hour to charge a completely dead pack roughly and you might want to raise the m/v by 2 because the false bumps will be more pronouced along with the real delta peak (charge complete) in order to avoid false termination. However, I find 7 and 14 work all the time for me regardless of how fast or slow I charge. If the pack has been sitting dead for years and is in rough shape you might keep getting false peaks while breaking it back in, so if it does keep kicking the charger off then raise it by 2. Very rare to ever need to change thse though.

Feel the pack if you think it missed it's peak. Is it getting hot? If it's being charged fairly fast (say .5 amps or more for the above pack) it should be getting hot or very warm if the pack is being over charged. A slower amp rate then that might not get things hot though so watch the capacity being put back in. It's not uncommon for a good pack to hold 300 to 500 more MA but if it's way past that then it probably missed it. Or watch the voltage and write it down. Come back 30 minutes later. Is it the same or lower? It should be rising over time. Check again in 20 or 30 minutes and see.

I'll point out real quick that you'll notice the charger turns the amp rate on and off here and there for a few seconds at a time and the voltage will drop because of that. This is a normal charging process. Wait until it's pack on and the voltage has climbed and stabilized to note the number.

More perhaps today on a link to the manual and the cigarette lighter adaptor, then we'll be diving into setting the nimh/nicad charging functions and doing the stock pack, excercising it as well with the discharge function or a car light bulb.

 

[Critterhunter]

Here is the manual for this charger...

http://www.sparkfun.com/datasheets/Prototyping/Batteries/ACCUCEL_manual(2).pdf

It can be confusing in some areas being a translation. Note! Do NOT rely on the Auto functions to automaticly set things like amp rates or the m/v setting, which I think it lets you set them at so it will decide. I found them very flaud in use on packs in certain cases.

Here is a great long thread on this charger in a RC forum that was started when it first came out. A lot of confusion was cleared up there on things in the manual and other fuzzy areas...

http://www.rcgroups.com/forums/showthread.php?t=886698

Again, ignore those who are using the hidden voltage calibration function. Unless you have a lab calibrated volt meter you'll never tweak it more accurate than from the factory, and I hear it's very good at accuracy and tolerances anyway.

 

[Critterhunter]

Here is the cigarette lighter adaptor for $2 from them. Make sure you read the comments from others under it as I didn't read to see if the plug polarity is correct for the Accucel 6. If you are also buying a dc power supply for in the house it would be a good idea to read those as well to see which ones have the right plug for the Accucel.

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=8819

NEVER charge in your car unless you are keeping a constant eye on things. In your house always in the middle of a cement floor or on a fire proof platform and place something like a clay flower pot over the charger/battery (must have an air vent like the hole in the pot's bottom) if you aren't going to watch it constantly. I just charge in the middle of my garage floor away from anything.

Not doing too bad at trying to keep things short and to the point, am I?

 

[Snagglepuss]

Critterhunter thanks for sharing all the great info