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Old 05-13-2011 | 07:14 AM
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Questions?? 4pk Life battery problem

Here is a weird one, I bought a Life pack from allerc for my 4pk cause I have a couple of coupons to use.

It came with rediculously sized plugs that are just inaapropriate for a TX battery, which this battery is labeled and sold for. I had to take off the shrink wrap and put on my own wires as 12 gauge is just a little too big for the futaba plug!

There is a PCB board in the battery which was unexpected but upon reading the paper that came with the battery it is so the battery can be charged from within the radio and with standard NiMH chargers.

The problem I have is I cannot get the battery to work. I went to cycle the battery and the chargers tells me the voltage is too low to cycle.

When I charge it says it is full even though it is not.

Additionally, when I attach a multimeter to the futaba end the cell reads 6.9 volts but for some reason, the radio will not turn on!

Should I just take out the pcb board? Not really sure what is going on here. This is the battery in question.

http://www.allerc.com/hyperion-lifep...ck-p-4724.html
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Old 05-13-2011 | 10:50 PM
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Can you run a straight life battery with no voltage dropping diodes?
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Old 05-14-2011 | 05:00 AM
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why not just splice the connector and wire to the thicker wire? i've done that before and it works fine. i think you went a bit too far on this one.
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Old 05-14-2011 | 09:56 AM
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This one is the best fitment for a 4pk/4pks: http://www3.towerhobbies.com/cgi-bin...&I=LXZTJ6&P=ML
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Old 05-14-2011 | 05:08 PM
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Originally Posted by j_blaze14
why not just splice the connector and wire to the thicker wire? i've done that before and it works fine. i think you went a bit too far on this one.

I just didn't think there would be enought room in the bottom of the tray for that much extra wire, and it was thick!

I think I am going to just get rid of the pcb board and give that a shot. The instructions say that it allows the battery to be charged from inside the radio using the nimh charger but I wont ever be doing that. There is a voltage drop of .3 volts on the board itself but I don't think it will hurt anything running it without the drop.
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Old 05-14-2011 | 05:14 PM
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I dont really understand how they can claim that it can be charged on a stock TX nimh charger

Must be a smart PCB if it handles a cc/cv charge cycle that a decent charger with a specialised Life mode would use

Fully charged 2s Life pack will be around 7.2v (3.6v / cell with a nominal voltage of 3.3v /cell)

Cheers
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Old 05-14-2011 | 09:45 PM
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How does that compare to a fully charged nimh pack?
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Old 05-14-2011 | 10:33 PM
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Not familiar with your radio

I assume it takes 8 AA cells, which would be 12v for alkalines or 9.6v for rechargeables

I would have thought a 3s Life pack (9.9v nominal, 10.8v fully charged) would be what you are after


I run a Spektrum radio and use LSD (Low Self Discharge) nimh AA cells

They come off the charger at 1.45v each (5.8v total)

I get 8 hours or so of operation before I bother to charge them back up

I have my transmitter low voltage alarm set at 4.6v and never hit it

Cheers
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Old 05-14-2011 | 11:28 PM
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it uses a 5 cell nimh pack. I tried to make a AA pack but the tray is too narrow for traditiolnal AA cells.
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Old 05-14-2011 | 11:54 PM
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Fair enough

5 cell nimh pack would have a nominal voltage of 6v, 7.25v straight off the charger

2s life would be fine in that case

Cheers
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Old 05-15-2011 | 10:46 AM
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I know you can solder and not destroy anything. I would just take off the board, I think that's what's causing your problems. My Protek Life packs for my radio don't have a PCB and they work perfect.
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Old 05-16-2011 | 10:38 AM
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Took off the board and it is working fine. Funny that I could put a meter on it and read a voltage but it wouldn't power up the radio. I wonder if the board was limiting the current too much?
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Old 05-16-2011 | 11:27 AM
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Just don't try to use the Futaba wall charger now as you have removed that feature. Use a regular LIFE charger.
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Old 05-21-2011 | 02:36 AM
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Originally Posted by golferdude1971
This one is the best fitment for a 4pk/4pks: http://www3.towerhobbies.com/cgi-bin...&I=LXZTJ6&P=ML
is this the BEST replacement batt for the OEM 1700 mah one??
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Old 05-21-2011 | 07:46 PM
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If I didn't have the coupons I would have ordered this.

http://www.amainhobbies.com/product_...ck-66V-2100mAh
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