would this battery work?

[Mike T]

On Ebay I found a 6800mah 12v rechargeable Lithium battery w/charger. It has the same connector as my Minelab Sovereign XS. Would it work? or would it fry everything?

 

[Critterhunter]

If the battery is a 3 cell series pack for a total of say 12.6V at full charge (on a lipo, but lithiums are a bit lower in voltage I think per cell..just don't want a pack that puts out any higher voltage then that due to the number of cells in series) then it should work fine. Are you sure it will fit your battery holder? It should I would think, because the XS I think used 10 huge Sub-C nicads in the compartment with no problem. has to be smaller than that for sure as lipos/lithiums are much smaller than nimhs or nicads and with much higher capacity.

Make sure the plug has the right polarity. Check it with a volt meter and see if the inner contact is positive and the outer negative or is it the reverse of that? Then check your XS to see if it's got the right polarity too (by looking for a marked indicator on the box or by testing an old XS pack with the volt meter). Most multi meters will say "-12V" (negative 12 votes for example) if the polarity is wrong when checking the contacts, so you'll know which is positive and negative that way. If you don't have a multimeter harbor tool and freight stores have decent ones for like $5.

If you want send me a PM with a link to that battery and charger and I'll check it out for you to see what else I can find out.

One other thing. Although lithiums are light like lipos, that size of a pack is needless huge in capacity. A 2000ma pack for example should give you about 40+ hours of run time between charges and be much lighter than 8AAs even. I'm running a 3 cell Rhino lipo that is only 750ma in my GT and I'm getting longer run times than the stock 1000ma pack. Reason being that a lipo holds it's voltage high to the end of discharge where as it drops faster on regular batteries or nimhs or nicads as they drain, so even though the stock pack is a bit higher in capacity it trips the low battery alarm faster due to the faster falling source voltage.

Also, be sure of when the low battery alarm kicks in on your XS. I bet it's the same as the GT, which I measured at about 10.2 to 10.5V from memory. You don't want to drain a lipo/lithium below 3V per cell (9V total). Can't remember off hand if lithiums have the same voltage cut off point as lipos. It might be a tad bit lower or higher than 3V per cell. What I'm saying is that you want to make sure the low battery alarm kicks in before the pack is drained below what is safe to not ruin the battery. With around 10.2 to 10.5 or so on the GT, I'm sure it's the same voltage regulator specs for all the Sovereigns I would think.

The battery sticky has thread links to lipo conversion for the XS and GT and such, which you might find helpful to read and fill in some questions you have. Those links are listed as being for lipo conversion info. Kered took some nice pics of his lipo installs in his XS and GT. I beat him to converting my Sovereign to lipos but never posted the pics on the project. It's simple and easy. Just have to solder a tiny plug into the 8AA holder, but in your case it sounds like you won't even need to do that because it sounds like that pack has a matching plug to your XS.

Again, don't take my word on any of this stuff. Always confirm and verify on your own.