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I just ordered 2 of them for both my radios.. been using eneloops but my charger (Imax B6) cuts well before they are charged. So I've been using an old nicad charger, set to charge at 10% of the eneloops capacity and let it charge over night.. the thing is, I have that old problem, sometimes the charge goes down at the field when before you thought you had enough juice for the day.. The LiFe batteries allow you to charge at least at 1C so even at the field if the voltage goes down it doesn't take long to top it up again.. My charger has LiFe mode, so I guess I'm ok.. I just need to trust them..

João

Can you program the delta amount on the charger so it fully charges thr NiMh cells. Or charge as much as you can, then top up at a low rate. I use Vapex cells, same as eneloops just cost a lot less and have 2500mAh capacity. I charge these at 700mA through the charge socket on the Tx. If necessary, a 10 minute charge at the field will give 30 minutes of flying.

Mike.

why every one is so into how to charge Tx batt in the field
spend 6.50 for one extra 3S LiFe from HK as spare. stick in the pocket (or where ever you deem fit ). it will last a whole day flying when your tx batt run out. I don't think I ever run a fully charged LiFe out in a day to begin with. Have a spare just in case something went wrong if the one in Tx go south.

MikeB wrote:Can you program the delta amount on the charger so it fully charges thr NiMh cells.

Tried that Mike, no luck.. That's what I don't really understand.. that charger doesn't like the eneloops, don't know why and even if I charge at 10% will stop the charge.. the other charger does the same. I have to set it to timed charge mode and let it charge all night.. But now it doesn't matter because I ordered the LiFe. Let's see how lucky I am with them. First step is for them to get here then I'll go from there...

João

This is the common problem of EV'S. Car companies should produce better batteries that could sustain energy. We need higher capacity of chargeable batteries. Nissan is still not admitting there is anything wrong with the battery packs in its electric Leaf. However, a group of owners in Arizona recently analyzed a perceived acceleration of charge capacity degradation in the battery packs, and found the packs lacking. However, Nissan is still getting back two of the cars with the state's lemon law.

Just curious jhsa ,
after the all night charge have you put a load on the pack 150-200 Ma as the TX would, or higher? Then as the pack discharges read the voltage drop across each battery as well as the whole pack. It's possible that your cells, or a cell in the pack is defective and spoofing the charger to think the packs charged. Also while charging all cells should have about the same cell reading. If one is way higher I would suspect it's damaged and just floating high and no longer has a low internal resistance. I've used Sanyo Eneloops for several years now and they act normal on my various smart chargers and ho;d their charge. I did speak to a Sanyo Rep and he told me the reason the Eneloops are only 2000 MA is to keep the chemistry and cell separators balanced. Any higher and the cells performance suffers. I have switched to Life04 1500Ma now for price reasons but my Eneloop packs do their job and charge OK. I'd question your batteries, not the chargers?
SM

My LiFe batts should be here this week, then I can take the eneloops out of the shrink and test them..

hey guys, maybe it was posted here before but what voltage should I set the battery alarm with these LiFe 1500mAH??

Thanks

João

I set mine at 8.6v. < 2.8v/cell will cause damage for LiFe. but I guess depend on the voltage sensor on the Tx. When mine reach 8.6v and the alarm sounds, I measure with voltmeter, each cell is right at 2.8 or 2.79. when it sounds, voltage drops fast (enough to land though). Mine when that sounds the cell volt drop to 2.8+- which is the lowest you can get. LiFe has a very even discharge plateau but it hits the edge it is like falling off a cliff.
so you may want to up that a little. but give it a run and check with voltmeter.
for 3S LiFe, that alarm is basically to protect the LiFe from being damaged, you have plenty of voltage to use the Tx.

that's what I meant.. to protect the battery.. these batteries can be charged in so little time.. it's just not worth it to run them too low.. Maybe a good alarm would be 9V, the same as for the eneloops..

João

9V is good. I think each batt is also a little different. try to run it down a few times and measure with a meter. I have 4 of them , each is a little different when that plateau/cliff starts. But you will find out with audio, your batt will run out a lot faster.

yeah, it's normal, but it depends on how much you use the audio.. if you have background music, of course the batt charge won't last very long..
I switch the audio telemetry once in a while just to know the flight pack status..

With all that trouble making the mod just to hear the flypack?
let me exchange my 2.00 lipo warning beeper with all your mods made.

i mean, turn the switch on to hear the info i need. At the moment i only have voltage sensors. Oh, and temperature. I also like to hear the plane's engine.

I thinking of having mine say" I'm not a Spektrum, enjoy your flight"



ShowMaster
Sent from my iPod touch using Tapatalk

what a wonderful idea.. that would p*** my friends right off..
But mine would say Futaba he he..

jhsa wrote:what a wonderful idea.. that would p*** my friends right off..
But mine would say Futaba he he..

can you really mod the radio to do stuff like that ? AND WHY CANT WE USE A LIPO ? THANKS

For the 9x a 3cell lipo is Ok but the stock FW low battery alarm is hard coded and will be wrong. After er9x/open9x FW update the alarm can be a custom value.
Many brands of others tx also have a hard coded low bat alarm. The life battery is a 9.9 v battery and will be more in line with the alarm settings.

There is a concern that many TXs were designed for a 10v range and the extra 2 volts the lipo provides may overheat some components and cause premature failure. Also more heat dissipated in the tx case that could cause drift.
Then the is the lipo fire concern that many worry about. Less of an issue all around with the life04 chemistry.
The unmodified B1 regulators on the sky board however is happier with a 2 cell lipo voltage. After the mod not an issue.
So...
Lipo
Fire concern
To much voltage 3 cell, maybe not enough 2 cell for some TXs.

Life
Less fire danger and a 3 cell is 9.9 v much like a nicad pack range. Sort of a sweet spot for a battery!
2 cell may be to little a voltage for some TXs.
It's your choice if it fits the voltage range and your ok with the safety concerns I'm thinking?




ShowMaster
Sent from my iPod touch using Tapatalk

Gavinxman wrote:

jhsa wrote:what a wonderful idea.. that would p*** my friends right off..
But mine would say Futaba he he..

can you really mod the radio to do stuff like that ? AND WHY CANT WE USE A LIPO ? THANKS

Yes you can, check it out..

[BBvideo 425,350]http://www.youtube.com/watch?v=1EVlo8qZ ... ature=plcp[/BBvideo]

jhsa, SM, and gavinxman:
view this and: Do you have any doubt any more?

sorry, off topic, just can't help it.

by the way, the 'star' wav file is copied into the Tx SD card directly through USB port without removing the card at all.
http://www.youtube.com/watch?v=ED3OH7VVnQs

No comments

A) Yes, the "servo type" connector fits the 9X radio, and is wired correctly. Even if you put it in backwards, it would simply not be connected and turn on. That said, it is ALWAYS a good idea with Chinese goods to double check the polarity of original battery pack vs. what you received before connecting up.

-Gyro

the 9x radio has 3 pins connector for battery input, the center is positive and both outer connections are ground, "So with the LiFe supplied servo connector" both directions will function fine, as center is positive and "BOTH" outer connection are ground. I solder my Li-Ion pack the circuit board for a more reliable connection.

but for a lower cost solution use two 18650 Li-Ion cells.
viewtopic.php?f=25&t=1143

Oz

ShowMaster wrote:There is a concern that many TXs were designed for a 10v range and the extra 2 volts the lipo provides may overheat some components and cause premature failure. Also more heat dissipated in the tx case that could cause drift.

Mr ShowMaster,

I thought the same thing, extra voltage = extra heat and YES it true,,,,,,BUT, it does not matter, I checked the temp and zero problems with temp (good pcb ground thermal heat sinking), but I prefer the 2 cell Li-Ion 18650 cells for many reasons, cost, weight, temp, safety etc.

See my temp testing here, results about the 13th post.
viewtopic.php?f=25&t=1143

Ozzy