RCU Forums

RCU Forums (https://www.rcuniverse.com/forum/)
-   Batteries & Chargers (https://www.rcuniverse.com/forum/batteries-chargers-84/)
-   -   Best way to test / check LIFE batteries? (https://www.rcuniverse.com/forum/batteries-chargers-84/11578919-best-way-test-check-life-batteries.html)

Ernie Misner 07-24-2013 02:48 PM

Best way to test / check LIFE batteries?
 
I have a couple of LIFE receiver packs from Tower, and a couple of cheapie 700mah LIFE packs from HK. I want to charge, then discharge them safely and see how much comes out of them. These are 6.6V rx packs. What is the lowest safe voltage to discharge them to? If the battery is rated at 700mah how much should you see come out of a LIFE pack?

The reason I am asking is because with my Nimh packs when I discharge down to .9V per cell I do see the proper amount come out of them. But with my 700mah Life packs I am only seeing 205mah come out when going down to 5.4V. Does this seem right? Thanks a bunch!

aghost 07-24-2013 03:53 PM

RE: Best way to test / check LIFE batteries?
 
I go to 5.1V (2.55/cell) when I discharge my LiFe rx packs (7 batteries - 2300 and 1100 mah). Seems like that gets to the 90 - 95% of mah available, but I don't remember for sure. My packs are from Hangtime Hobby. I get close enough to the rated mah to be satisfied. Been using most of the packs for a couple of years now.<div>
</div><div>Brian</div>

Ernie Misner 07-24-2013 05:06 PM

RE: Best way to test / check LIFE batteries?
 
Thanks Brian. Info with the Life's from Tower says never to go below 5.0V or they could be damaged. Maybe we shouldn't go quite so low? Let's see what others say too. Thanks again.

aghost 07-25-2013 04:45 AM

RE: Best way to test / check LIFE batteries?
 
Added note.<div>
</div><div>I generally discharge at 0.5C or less. charge at 0.5C or 1A whichever is less. I know the batteries are rated for higher values, but I rarely have a need to push them.<div>
</div><div>Brian</div></div>

raptureboy 07-25-2013 06:49 AM

RE: Best way to test / check LIFE batteries?
 
Here you go, all you need to know and from one of the best in the business http://hangtimes.com/a123_batteries_for_giants_faq.html

RAMFlyer 07-25-2013 03:41 PM

RE: Best way to test / check LIFE batteries?
 
EDR-207 http://electrodynam.com/rc/EDR-207/index.shtml

Ernie Misner 07-25-2013 05:00 PM

RE: Best way to test / check LIFE batteries?
 
GREAT A123 links guys!!!

Ernie Misner 07-25-2013 05:30 PM

RE: Best way to test / check LIFE batteries?
 
They are saying not to go below 5.0V when discharging/testing AND not to expect a 1100mah battery (for example) to have 1100mah come out when testing using this method like with other chemistry. (the 5.0V cutoff is conservative for safety)

drube 07-26-2013 07:32 AM

RE: Best way to test / check LIFE batteries?
 
Are A123's the same as LiFe batteries?

acdii 07-29-2013 05:53 PM

RE: Best way to test / check LIFE batteries?
 
Here's a question, is there any harm to charge it up after a few flights even though there is still plenty of LiFe left?

Ernie Misner 07-29-2013 09:54 PM

RE: Best way to test / check LIFE batteries?
 
No harm whatsoever and they don't exhibit any memory effect. I think the general rule is that if they are full it's not a good idea to top them off again though.

4*60 07-29-2013 11:44 PM

RE: Best way to test / check LIFE batteries?
 
I get almost the capacity when discharging 1100 and 1800 HK LIFE packs.
I have some A123 1100 packs and I get just over 800 out of them and that was right from new but the a123 can stand higher loads in use.

BarracudaHockey 07-30-2013 06:21 AM

RE: Best way to test / check LIFE batteries?
 


ORIGINAL: drube

Are A123's the same as LiFe batteries?

Yes and no. The chemistry is similar.

A123 is a brand name, like Tylenol is for acetaminophen.
A123 systems cells use nano technology that allows greater charge and discharge rates, and IMO are all around better cells.

The downside is they are available only in the hard pack cells of 2300, 2500 and 1100 Mah capacity and the form factor is set.


carl24bpool 07-30-2013 06:38 AM

RE: Best way to test / check LIFE batteries?
 
Okay guys. I've tried to get y head around it but I'm strugging with the wordin in my manual and online.

I have a 9.6v Ni-cad and a 4.8v nicad. The 9.6 is rated 600mA and so it the 4.8.

They are quite old so I want to tyr cycling them so see if htey are of any use.

What do I set the charging current to and what do I set the discharge voltage to? I read discharge is 0.85v per cell. Is that right?

Also how does the charger know when they are charged and to start discharging? I don;t get that bit. Do I need to set an upper limit or not? I can;t see how the charger knows how many cells there are so when to stop charging at what voltage.

I read about something called delta peak sensetivity. Can somebody explain this in simple terms please?

Also to give me an idea how long should 5 cycles take? Am I looking at 16 hours for each charge so were talking days?

carl24bpool 07-30-2013 06:42 AM

RE: Best way to test / check LIFE batteries?
 
sorry guys, this was supposed to be in a new thread. I can;t seem to remove it either.

Mods?

BarracudaHockey 07-30-2013 06:44 AM

RE: Best way to test / check LIFE batteries?
 
http://www.swgiantscalemodels.com/st...671&pd=4994149

These testers give a remarkably accurate representation of whats left. They agree within a percent or so of the calculated capacity when I hook them up to my cellpro to charge.

ORIGINAL: drube

Are A123's the same as LiFe batteries?

Yes and no.

Same chemistry, but A123's are a brand name made by A123 systems, that use nano technology and support higher charge and discharge rates. A123 cells are IMO better. Though many LiFe cells are good enough for us.

Ernie Misner 07-30-2013 03:45 PM

RE: Best way to test / check LIFE batteries?
 
>>>> http://www.swgiantscalemodels.com/st...671&pd=4994149
These testers give a remarkably accurate representation of whats left. They agree within a percent or so of the calculated capacity when I hook them up to my cellpro to charge. >>>>

Thanks for the info on that popular little tester. I have one already so it's good to hear that they are accurate with Life batteries. When any of my Life battery is freshly charged they never near 100% on that tester though; guess that is the way it is. Another note on that tester - although it has an input for nicads and nimh, it does not test them under any kind of a load which is not an accuate test for that battery type, right?

ThunderBoat42 07-30-2013 04:00 PM

RE: Best way to test / check LIFE batteries?
 
GREAT LINKS... hours of reading for sure.  <div>
</div><div>I have an add on question....  I also have the LiFe source pack from Tower.   ....   What is the balancing connector type.  It say "electrifly"   </div><div><em style="font-family: Arial, Helvetica, sans-serif; font-size: small; background-color: rgb(204, 204, 204);"><font color="#000000" face="Arial,Helvetica,sans-serif">JST-XH or </font>FMA [/i]</div><div><em style="font-family: Arial, Helvetica, sans-serif; font-size: small; background-color: rgb(204, 204, 204);">
[/i]</div><div><font size="2" face="Arial, Helvetica, sans-serif">there seems to be about 3 types out there!!!   long to RC but new to this.  I purchased and X4 acdc charger that I really like.   </font></div><div><font size="2" face="Arial, Helvetica, sans-serif">
</font></div><div><font size="2" face="Arial, Helvetica, sans-serif">I am doing a warbird and want to run 2 batteries....  with charge AND balancing jacks.  I may end up running 3 for the electric gear... but for now.. just 2.  </font></div><div><font size="2" face="Arial, Helvetica, sans-serif">
</font></div><div><font size="2" face="Arial, Helvetica, sans-serif">
</font></div>

Ernie Misner 07-30-2013 04:10 PM

RE: Best way to test / check LIFE batteries?
 
JST-XH or FMA ....... that is the funny little balancing plug type. Does your charger have a different type of balancing plug? You can get an adaptor. Most chargers including the Tower Life charger comes with this type. Hint: an extension cord for that balancing plug makes in-plane charging/balancing easier for me. I pick them up at the hobby expos.

ThunderBoat42 07-30-2013 04:41 PM

RE: Best way to test / check LIFE batteries?
 
The X4 comes with all types.   So I can charge it just fine out of the plane.  <div>The extensions are all over ebay and suppliers I just dont know which one this battery is Life pack from Tower.  Taildraggerrc.com has the 24" Jst-xh extension for $4.00</div><div>
</div><div>
</div><div>I since its a 2 cell battery I was going to cut it and use the 3 wires of the futaba standard through fuse charge jack to each half and balance in the plane.  One half with a futaba male.. the other with a futaba female.  </div><div>
</div><div>
</div>

Ernie Misner 07-30-2013 05:15 PM

RE: Best way to test / check LIFE batteries?
 
>>> I since its a 2 cell battery I was going to cut it and use the 3 wires of the futaba standard through fuse charge jack to each half and balance in the plane. One half with a futaba male.. the other with a futaba female. >>>

How exactly do you do that? Then only need the one stock charge cord with JR type std. plug to charge and balance both at the same time?

acerc 07-30-2013 05:38 PM

RE: Best way to test / check LIFE batteries?
 
I just did similar on a build. LiFe battery with an adapter on the balance plug, just had to make sure the current was correctly carried throughout to the balance port.

ThunderBoat42 07-30-2013 06:36 PM

RE: Best way to test / check LIFE batteries?
 
Exactly Acer....<div>
</div><div>Earnie...here is a site I found with combo plugs...   batteries are a little high though.   I am wanting to go with what Acer did there x 2</div><div>http://hangtimes.com/a123_packs.html</div><div>
</div><div>I have these for the charging/switch... they work great    http://www.swgiantscalemodels.com/st...amp;pd=4998662</div><div>
</div><div>I used these guys for the Y's and servo extensions....  20 ga ... 100 strand and excellent quality</div><div>http://www.taildraggerrc.com/servo-e...ccesories.html</div>

ThunderBoat42 07-30-2013 06:38 PM

RE: Best way to test / check LIFE batteries?
 
I still dont know what type of Balance connector is needed for the Tower supplied LIFE Pack though.  <div>
</div><div>FROMCO has a 1 amp load tester for the battery I like too.   </div><div>
</div><div>While not exactly the same as the thread topic.. there are a lot of people trying these batteries with questions ...   I LIKE them.  even though new to the technology.</div>

RAMFlyer 07-30-2013 07:35 PM

RE: Best way to test / check LIFE batteries?
 
JST XH http://www.rcaccessory.com/pdf/Batte...%20Guide.pdfIf you are talking about the Hobbico LiFe batteries...


All times are GMT -8. The time now is 10:19 PM.


Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.