Etrac and lithium ion rechargeables

Marjam42

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I was looking to see if the rnb innovations battery pack was available, and I appears everywhere I looked is out of stock. I wondered if anyone has went and bought the rechargeable lithium ion AAs that you can get at the big box stores and compared them to see if they are as good as the rnb pack? Both are lithium ion, so just wondered if they are comparable.

Thanks for any info you can provide.

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A quick $15 fix for the FBS machines is 8 AA NiMH rechargeable batteries from Harbor Freight, along with a terminal spring from a old TV remote to complete the connection on one end...installed in the original rechargeable battery pack case. It'll now last for at least 18 hours on a charge, and the factory charger can still be used...
 
I was looking to see if the rnb innovations battery pack was available, and I appears everywhere I looked is out of stock. I wondered if anyone has went and bought the rechargeable lithium ion AAs that you can get at the big box stores and compared them to see if they are as good as the rnb pack? Both are lithium ion, so just wondered if they are comparable.

Thanks for any info you can provide.

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There are a few RNB's on Fleabay, for Minelab FBS....
 
A quick $15 fix for the FBS machines is 8 AA NiMH rechargeable batteries from Harbor Freight, along with a terminal spring from a old TV remote to complete the connection on one end...installed in the original rechargeable battery pack case. It'll now last for at least 18 hours on a charge, and the factory charger can still be used...

I did the same for my used Explorer II.
 
I was looking to see if the rnb innovations battery pack was available, and I appears everywhere I looked is out of stock. I wondered if anyone has went and bought the rechargeable lithium ion AAs that you can get at the big box stores and compared them to see if they are as good as the rnb pack? Both are lithium ion, so just wondered if they are comparable.

Thanks for any info you can provide.

Sent from my SM-G975U using Tapatalk

Try the rechargeable 1.5v LiOn AA cells that are much better than the NiMh 1.2 v batteries. Lighter too.

Check these out:

https://www.amazon.com/dp/B08F3FC3G...lja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ&th=1

Charge anywhere you have access to USB power, or use a power pack.

Hope this helps...

 
Thanks for the link. I see that on the rnb innovations website that the battery pack is in stock. Still undecided which way I will go, but I appreciate the information.

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A bunch of dealers have the rnb innovations back in stock now.

Make sure you check the pricing. I just bought one and payed way to much.
 
A bunch of dealers have the rnb innovations back in stock now.



Make sure you check the pricing. I just bought one and payed way to much.
What should you expect to pay for one? Rnb has them for 139.

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Big Boys Hobbies is showing them in stock for $89.21. They also sponsor this place.
Do you have a link for this price for the etrac? I just went there and its $139 and showing out of stock.

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Do you have a link for this price for the etrac? I just went there and its $139 and showing out of stock.

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Nevermind, I found it. I didnt know they had the 3400 model. Its cheaper than the 3100, their older version. Thanks for the heads up..

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Try the rechargeable 1.5v LiOn AA cells that are much better than the NiMh 1.2 v batteries. Lighter too.

Check these out:

https://www.amazon.com/dp/B08F3FC3G...lja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ&th=1

Charge anywhere you have access to USB power, or use a power pack.

Hope this helps...


Thanks for the posting ... Would these be able to be used in the minelab 12V slimpack designed for the 1.5AAs. Just came across this thread and have been considering some options. :?:
 
Thanks for the posting ... Would these be able to be used in the minelab 12V slimpack designed for the 1.5AAs. Just came across this thread and have been considering some options. :?:

Should work fine. Physical size is AA, voltage is ~1.5V. The good news is it is a constant 1.5V until the battery is needing recharge. The bad news is it is rated at 1950mAh.

A plain jane duracell alkaline has about 2500mAh in a metal detector. NiMH rechargeables vary, but go up to 2300-2500mAh on the high end.

The higher the mAh, the longer the runtime. If your detector runs fine on the 1.25V of NiMHs, that seems the best option to me. If you feel it it runs better on "full voltage" and you want rechargeable, the Li-ion AAs seem like just the ticket. But I'd expect them to only run about 80% as long as alkalines or the NiMHs do. Close enough, you probably won't notice.
 
Should work fine. Physical size is AA, voltage is ~1.5V. The good news is it is a constant 1.5V until the battery is needing recharge. The bad news is it is rated at 1950mAh.

A plain jane duracell alkaline has about 2500mAh in a metal detector. NiMH rechargeables vary, but go up to 2300-2500mAh on the high end.

The higher the mAh, the longer the runtime. If your detector runs fine on the 1.25V of NiMHs, that seems the best option to me. If you feel it it runs better on "full voltage" and you want rechargeable, the Li-ion AAs seem like just the ticket. But I'd expect them to only run about 80% as long as alkalines or the NiMHs do. Close enough, you probably won't notice.

Just purchased and received a minelab reconditioned e-trac. Starting to become a bit familiar with it. It came with the rechargeable NiMH & the AA cell Alkaline battery pack. So this discussion is interesting. Minelab cautions in the manual that there is an over load protection of above 13V built in for protection.

Correct me if I'm mistaken but I think that the rechargeable pack will put out 9.6V fully charged to operate the etrac. Not sure what the minimum voltage the e-trac can work at.

The information you provided concerning the Li-ion battery application is ideal. Also less time recharging them and they should hold their charge longer for a back up or primary pack usage at a consistent 12V. :yes:
 
Just purchased and received a minelab reconditioned e-trac. Starting to become a bit familiar with it. It came with the rechargeable NiMH & the AA cell Alkaline battery pack. So this discussion is interesting. Minelab cautions in the manual that there is an over load protection of above 13V built in for protection.

Correct me if I'm mistaken but I think that the rechargeable pack will put out 9.6V fully charged to operate the etrac. Not sure what the minimum voltage the e-trac can work at.

The information you provided concerning the Li-ion battery application is ideal. Also less time recharging them and they should hold their charge longer for a back up or primary pack usage at a consistent 12V. :yes:

Since ML's rechargeable pack is essentially 8 NiMH cells, which (when new) gives 9.6V more or less steady until needing recharge, the Etrac must be fine with that lower voltage. Probably good down to 8-9V or so to allow for aging, and use up alkalines as much as possible.

So the lithium ion AAs are sort of overkill voltage-wise -- that extra voltage may just get burned off by an old school voltage regulator inside the etrac -- further reducing the useful life of them. But yes, they claim to hold charge a long time, and if they recharge quicker than the NiMHs, that's a plus, too. There are low self-discharge (LSD) NiMHs that hold charge for a long time (at least 6 months as I recall) too, and you'd get much closer to the full claimed mAh out of them. This is a situation where I'd use rechargeable NiMHs, and good old alkalines as a backup.

Those li-ion AAs are a cool concept, but better for something benefiting from the full 1.5V per cell, like an unregulated flashlight, or a motorized toy...
 
Since ML's rechargeable pack is essentially 8 NiMH cells, which (when new) gives 9.6V more or less steady until needing recharge, the Etrac must be fine with that lower voltage. Probably good down to 8-9V or so to allow for aging, and use up alkalines as much as possible.

So the lithium ion AAs are sort of overkill voltage-wise -- that extra voltage may just get burned off by an old school voltage regulator inside the etrac -- further reducing the useful life of them. But yes, they claim to hold charge a long time, and if they recharge quicker than the NiMHs, that's a plus, too. There are low self-discharge (LSD) NiMHs that hold charge for a long time (at least 6 months as I recall) too, and you'd get much closer to the full claimed mAh out of them. This is a situation where I'd use rechargeable NiMHs, and good old alkalines as a backup.

Those li-ion AAs are a cool concept, but better for something benefiting from the full 1.5V per cell, like an unregulated flashlight, or a motorized toy...

Does that mean the Minelab 8xAA NiMH pack uses a regulator to maintain that voltage? A fresh, hot-off-the-charger 8 cell NiMH pack can easily be over 11 volts (unloaded reading).

Oh, and high quality LSD NiMH cells like Panasonic's Eneloops can hold their charge for years (think 70% after 10 years). I think it's 10% loss in 6 months and another 5% on top of that after another 6 months. In other words, a fully charged cell will have 85% of its charge after one year in storage.

Eneloops and other LSD NiMH cells of similar quality are where's it's at. Unless low weight or super-low-temp performance are needed in a mission critical application, there's little need to use lithium-ion or lithium-poly batteries in our detectors.
 
Does that mean the Minelab 8xAA NiMH pack uses a regulator to maintain that voltage? A fresh, hot-off-the-charger 8 cell NiMH pack can easily be over 11 volts (unloaded reading).

No, it's likely just 8 NiMH cells wired in series. Re-reading your comment, I understand better -- I meant the etrac *detector* probably has a voltage regulator in it, not the battery pack.

Fresh off the charger 11/8 = 1.4V which is believable. They drop pretty quickly to 1.3V, then very slowly drop for the remainder of their useful charge...found a graph. Pink is alkaline, see how it starts higher but keeps dropping. Black and blue are both NiMHs -- they hold flatter
 

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