Excalibur rechargeable battery pod tip

[Farmercal]

I found a easy way to drain the rechargeable battery pod on my Excalibur before re-charging. I had a 12 volt 80mm computer fan laying around that came out of an old computer. I cut the connector off of the wires, stripped the end of each wire to expose the copper ends and just pushed them into the battery end of the pod and let the battery run the fan until it was out of juice. Since I am an IT person by trade these fans are always available. Of course any component that utilizes 12 volts will work but the fan was easily available to me. HH Cal

 

[Art (NWOH)]

You're going to reverse charge some of the cells that way. This will damage your battery pack.

Never run a rechargeable multicell pack all the way down.

 

[Rick(ND)]

What a person needs to do is have some kind of a way to stop the discharge before it drains it completely and reverses the charge, then recharge right away. Sun Ray had a charger like this called the SR12 super charger ( I have one of these and wish they still made them).
I know of several that uses 12 volt bulbs too, but too unless you stop the discharge before it completely discharges you could ruin the battery which is easy to do when you forget to check it while discharging. We see many too that will forget the battery on the charger too and charge for 2 or 3 days before they remember it. I think this is why the Elite and the GT have a limiter in the battery pack to help from over charging and ruining the battery.

 

[Farmercal]

I didn't know that. From now on I will set the thing down next to me and keep an eye on it and when the fan start to slow enough that I am sure it's about out I will stop the discharge. I kept watching it drain and the fan couldn't have been off for more than hour before I charged it back up. I also charged the pod for about 12 - 13 hours and I heard someone say that its gets mega warm but when I checked it after the time was up, it was cool to the touch like it has something in there to stop charging after it get fully charged. When I measured the voltage it was at 14 volts and the charger was putting out 19 volts. The pod is new (perhaps two months old). Thanks for the information, that's why I ask you pros! Cal

 

[Art (NWOH)]

At least hook a voltmeter up to it. Stop the discharge at 9 volts.

You have to watch it pretty close. Once the voltage drops below 11 volts it will drop pretty fast. You need to be watching it.

Charging with the stock Minelab charger (trickle charge) for 12-14 hrs is about right. If you charge a little longer at this low rate you won't hurt the batteries.

Don't use a high powered charger or you will get the batteries very hot and ruin them. Minelab chargers are designed for slow trickle charge of just a bit more current than the detector itself would use. This is why it takes so long for a recharge, but there is less chance of cooking the batteries this way.

I have a home made discharger that I use for my Sov Ni-cd. It drains the pack down to 9 volts, then shuts itself off automaticaly.
It drains the pack at about twice the normal rate that the detector would.
I even drain the GT pack once in a while before recharge. Don't really need too (Ni-Mh), but like to give my packs a good workout once in a while. Recharge is done with a timer set for 14 hrs.

HH

 

[Farmercal]

Outstanding advice again Art! I will do just that and I only use the Minelab charger to charge them back to full capacity. Again, thanks for such good advice. I'm new at this detector and want it to last as long as possible to include the battery pod. HH Cal