F960/70/75 Li-ion Battery suggestions?

[bklein]

I've tried a few of the ebay Chinese Sony batteries for my Minelab Gp Extreme/Coiltek battery system and they don't perform near to their Ah marking.
Anyone know of a low cost alternate battery solution for this type battery that is like 7400Ah? Otherwise looks like I'll have to make my own.

[kellogs]

Hi kellogs hear iam only new to this hobby but i started off with a DUALSKY XP22003 2200mah 11.1 volt which purchased from a hobby shop and i have been on line and i think the do a model that you are after i why just type in DUALSKY and all the suppliers come up just a question as a newbe why shuch a high amh hope this is some help Regards Kellogs.

[golfnut]

Ive used reclaims from failed laptop batteries.


Often the cells are spot welded in parallel then series.


On parallel pair is normally bad, so you get a good few good ones.


Re package as appropriate, wire as a lipo pack for model flying, charge with a balancer charger

[kellogs]

Hi golfnut i bought mine with the charger in aus but being new didn't even think to look to see if available on line any way have bought 2 new lipo from hobby king 3s x 5200 ,mah for only $55.46 +delivery $16.46 pretty cheep. any way have a great weekend talk later Regards kellogs

[Chet]

I've tried a few of the ebay Chinese Sony batteries for my Minelab Gp Extreme/Coiltek battery system and they don't perform near to their Ah marking.
Anyone know of a low cost alternate battery solution for this type battery that is like 7400Ah? Otherwise looks like I'll have to make my own.

Hi bklein, You might find this site useful for battery selection.

http://lygte-info.dk/review/batterie...mary%20UK.html

[kellogs]

Hi Chet dont you think lipo batteries are good to use on surf pi i have been using 2200 mah 11.1 volt and seems to be working pretty good as you know i am only new to this and will take your advice on borad thanks once again Regards kellogs.

[Chet]

Hi Chet dont you think lipo batteries are good to use on surf pi i have been using 2200 mah 11.1 volt and seems to be working pretty good as you know i am only new to this and will take your advice on borad thanks once again Regards kellogs.

Hi kellogs, lipo batteries are fine. They pack a lot of power in a lightweight package. The choice of which batteries are best depends on different situations. Most detectors have voltage regulators that maintain critical circuits stable until the battery is almost exhausted.


The transmitter is usually run directly from the full voltage of the battery. The transmitter will perform well over a range of a few volts. In your case an 11.1 volt lipo battery fully charged may be close to 12.5 volts. It is probably ok to run on it until it is down to around 10 volts. The transmitter may be drawing few amperes on each pulse but the overall average detector power may run around 0.5 to 0.6 amperes.


A 2200 mah battery should provide 2.2 amperes of useful power for 1 hour. If the average draw is 600 ma then the battery should be removed for recharge at 2200/600 = 3.66 hours. If you refer to independent battery evaluation charts you will see that many batteries are overrated. So in this case 3 hours would be a good estimate to work with.


I don’t know the power drain of a Surf PI but the above example should give you some ideas to work with. If you don’t have a multimeter you should purchase an inexpensive one to check and monitor your battery condition. Then you will know how long you can run on a full charge.


This is where some decisions are made; do you want a battery to run continuously for 6 hours or intermittently a few hours over several days. Or do you want to carry a spare battery to change out after 3 or 4 hours. Adjust the battery mah size or number of spare batteries to fit your situation.


I have two spare batteries one in the car and one in a fanny pack. It is less weight to swing for hours at a time. Batteries frequently fail without warning. Too many of my friends waste days of outings because of battery problems. Many times they forgot to recharge or didn’t connect them properly to the charger. When they have the same as mine they use the spare that I keep in the car.

[kellogs]

Hi Chet wow thanks once again for your help and knowledge all of you are great this has helped me a lot as only have a few veteran mates left and don't see them so often i am looking at building another detector mainly for out bush what do you think what would be a good one to build any ideas any way mate thank once again have a great week end Regards kellogs

[Chet]

Hi Chet wow thanks once again for your help and knowledge all of you are great this has helped me a lot as only have a few veteran mates left and don't see them so often i am looking at building another detector mainly for out bush what do you think what would be a good one to build any ideas any way mate thank once again have a great week end Regards kellogs

Hi kellogs, I recommend reviewing the forums for the different results that others have had with the PI kits. Some are difficult to get working without an oscilloscope. I haven't had time to search through the forums enough to make a recommendation. For use in the Bush you need one that has a ground balance circuit to nullify some of the mineralized rocks and ground.

I recently built the Minipulse Plus kit and happy with bench test results. It is an easy one to build but it doesn't have a ground balance circuit. I am using an 8" (200 mm) basket wound coil described in the Chance PI forum. I am experimenting with it on the bench and hope someday to add some kind of ground balance circuit before I try it in the field.

A most important part of a good detector is a well built fast coil. Recommend you review some of the forums on coils and especially the basket wound coil in the Chance PI forum. If you build a coil, recommend that you stay under 8" (200 mm).

A used commercially built MONO coil such as Nugget Finder, Coiltek or Minelab will work well with most of the kits. For the best results I recommend that you keep the commercial coil size below 11" (281 mm) or below 9" x 14" (230 mm x 358 mm).

[kellogs]

Hi Chet thanks once again for your advice i will look through thes forums that you have suggested have a great day mate Regards Kellogs.