Cycling Nimh batteries - RCCanada - Canada Radio Controlled Hobby Forum
RCCanada - Canada's Radio Control Hobby Forum
Electronics Discuss radios, chargers, etc...

Reply
 
Thread Tools Display Modes
Old 05-14-2019, 10:01 AM   #1
Harvard 387
RCC Junior Contributor
 
Harvard 387's Avatar
 
I am: Don Forness
Join Date: Oct 2006
Location: Saskatchewan
Radio of choice:
hitec
# of RCs: 38

Feedback: 8 / 100%
Posts: 233
Total Props: 2
Cycling Nimh batteries


       Remove this ad - become a site supporter!
This is probably a pretty basic question for most but I am having a problem with a 1700 mah battery that I am working with. It is brand new and it only get about 150 mah into it on a charge.
I am using an older Triton charger set on "Auto" to charge and discharge the pack.

I also know that Nimh's need a couple of cycles before they store full power.

What do I need to set the Charge - Discharge rates at to properly cycle this pack and be reassured that it is OK to fly?
Harvard 387 is offline   Quick reply to this message.

Sponsored Links - Subscribe to remove this ad.
Old 05-14-2019, 10:10 AM   #2
floyd
RCC Supreme Contributor
 
I am: Floyd S
Join Date: Feb 2009
Location: Stayner, Ontario

Feedback: 188 / 100%
Posts: 3,411
Total Props: 13
Re: Cycling Nimh batteries

You don't need to cycle NIMH packs. But you need to condition the pack before fast charging other wise the charger will stop charging and the pack won't accept a charge. The first charge should be no more than 300mah, then after the charger stops charging drop the charger down to 200mah and continue charging until it stops. The pack should get warm and take a full capacity charge. During conditioning all my NIMH packs exceed their capacity. After the conditioning you should be able to charge at a higher rate. I never charge my 2300mah packs more than 500mah and mostly just charge at 400mah with no further issues. And over the winter my packs hold a good charge. Cheers Floyd

Last edited by floyd; 05-14-2019 at 10:21 AM.
floyd is offline   Quick reply to this message.
Old 05-14-2019, 10:20 AM   #3
Cougar429
Level 3 Supporter
★ Site Supporter ★
 
Cougar429's Avatar
 
I am: Gary L
Join Date: Aug 2008
Location: Tecumseh, Ontario

Feedback: 92 / 100%
Posts: 6,503
Total Props: 37
Re: Cycling Nimh batteries

Not sure, but does the Triton have a NiMH chem setting? Temp sensor input?

As mentioned, NiMH don't need cycling since they do not tend to build the "Memory" NiCads were known for. However, they have a different charge profile from NiCads since their voltage drops a bit once close to full so the temp increase is usually used to tell status. Otherwise the charger tends to see that as a lower charge percentage and tries to pump it up even higher, to the point of overheating.
__________________
I know there's money in aviation........I put it there!
Cougar429 is offline   Quick reply to this message.
 
Old 05-14-2019, 11:30 AM   #4
michaely
RCC Master Contributor
 
I am: michael o
Join Date: May 2013
Location: newmarket, ontario L3Y 1H1
Radio of choice:
JRx8103, FrSky Taranis & Horus 10x
# of RCs: 20

Feedback: 49 / 100%
Posts: 1,015
Total Props: 8
Re: Cycling Nimh batteries

I have found C.L. "Red" Scholefield's Hangtimes.com website to be the best information source on batteries we use for other than powering motors.

Check out this extended thread:http://www.hangtimes.com/rcbattery_faq.html
and, more specifically, scroll down about midway to a Q&A where he specifically answers your question about the Triton not completely topping up a user's Nimh battery.... it appears that the factory default cut off setting on charging Nimh's is 1000ma and your need to reprogram the charger, with instructions on page 14, item 8.


Also he has a review of the Triton charger on his "battery clinic" page.


I have a very smart charger for my lipo/LiFe batteries but for convenience/simplicity, with Nimh and NiCad airborne packs I use legacy ACE R/C Digipace II and Hobbico "battery analyzers"..... which I've bought at swap meets for $5 or $10.

I also use, for NiCad or Nimh airborne battery packs, an expanded scale voltmeter (ESV) at the flying field to ensure there is enough capacity left for a third or fourth flight, as the ESV's put a 250 or 500ma load on the battery to emulate the drain of the servos and rx.... again an item you typically can buy privately for 5 bucks.


Also, you may want to explore LiFe batteries for powering airborne electronics as it is the new kid on the block.
__________________
Michael
Newmarket, Ontario
MAAC 15048

Last edited by michaely; 05-14-2019 at 11:37 AM.
michaely is offline   Quick reply to this message.
Old 05-14-2019, 12:03 PM   #5
Cougar429
Level 3 Supporter
★ Site Supporter ★
 
Cougar429's Avatar
 
I am: Gary L
Join Date: Aug 2008
Location: Tecumseh, Ontario

Feedback: 92 / 100%
Posts: 6,503
Total Props: 37
Re: Cycling Nimh batteries

I have been using LiFE batteries for both transmitter and flight packs for the last several years and will not go back. Their advantages far outweigh the cost and in the case of Tx packs less than NiMH of the same or greater capacity. They also rewind very rapidly and retain charge almost indefinitely.

Only disadvantage is if you are still running 72MHz with the Tx antenna extended as balance can be off. There are clip adapters to reset the balance point so not a show stopper.
__________________
I know there's money in aviation........I put it there!
Cougar429 is offline   Quick reply to this message.
Old 05-14-2019, 12:05 PM   #6
Max
Administrator
★ Site Supporter ★★ Administrator ★
 
Max's Avatar
 
I am: Max P.
Join Date: Feb 2007
Location: Aurora, Ontario
Radio of choice:
JR and Spektrum

Feedback: 44 / 100%
Posts: 16,721
Total Props: 170
Re: Cycling Nimh batteries

CHARGE SLOW!

I find NiMh needs cycling to get it back to snuff. Floyd calls it "Conditioning" and maybe that is what is a better way to describe it, but to condition it I would cycle it.

Here is how I would do it:
  1. For your 1700mah pack, I would charge it at 150mah. This will take overnight.
  2. Then let your pack sit for 1/2 day.
  3. Then discharge it at 500mah
  4. When it is done discharging, let it sit for at least an hour
  5. Recharge at 150mah overnight. Your pack should take in about 1700mah when the charge cycle is done.
__________________
RC Test Pilot; FPV Instructor, Airplane Instructor; Helicopter Instructor

My Aircraft Albums: https://www.rccanada.ca/rccforum/album.php?u=13173

Last Photo added: Dec 15; Warwing Foamy for FPV
Max is offline   Quick reply to this message.
Old 05-14-2019, 03:02 PM   #7
floyd
RCC Supreme Contributor
 
I am: Floyd S
Join Date: Feb 2009
Location: Stayner, Ontario

Feedback: 188 / 100%
Posts: 3,411
Total Props: 13
Re: Cycling Nimh batteries

When I find a low voltage NIMH pack I throw it out. My good packs hold a charge all through the winter months. Because they don't need to be cycled I find you can never get the capacity back. My 2800mah transmitter pack alarmed after 120 minutes of flying several seasons ago, the pack was scrap as it didn't hold a good charge any more, but it was over ten years old. That's usually how a NIMH pack goes bad. In my planes I don't take a chance. But I have some packs well over ten years old without any issues yet. I check my RX packs at the field with a volt meter. Cheers Floyd
floyd is offline   Quick reply to this message.
Old 05-14-2019, 04:07 PM   #8
Mike Sebastien
RCC Supreme Contributor
 
Mike Sebastien's Avatar
 
I am: Mike s
Join Date: Sep 2005
Location: Moncton, NB

Feedback: 22 / 100%
Posts: 2,688
Total Props: 15
Re: Cycling Nimh batteries

These guys are right you don't have to cycle NIMH's like Nicads but sure nice to find out if they are up to snuff.

Pull my old Triton charger out of my garbage box and put a new Enevolop Nimh pack on it to discharge. Set it to Auto and started to discharge the Battery pack. It was only pulling 0.1 amp out of the pack and would have taken at least a day to discharge. I Stopped the discharge after 1 hour and set the triton discharge to manual @ 0.5 amps. It worked better but..... If anyone wants a Trton charger free of charge come get it. Local pick up only.

Not sure if your battery pack is good, when in doubt turf the pack. Batteries are cheap, airplanes are expensive.

They are much better chargers at really good prices that are available Treat yourself
__________________
Mike
Per Ardua Ad Astral
Mike Sebastien is offline   Quick reply to this message.
Old 05-16-2019, 09:14 AM   #9
kip51035
RCC Supreme Contributor
 
kip51035's Avatar
 
I am: Cliff S
Join Date: Feb 2007
Location: Belleville Ont.
Radio of choice:
Hitec, Futaba - FM
# of RCs: 10

Feedback: 25 / 96%
Posts: 3,074
Total Props: 15
Re: Cycling Nimh batteries

Do not cycle NMHI batteries!!! When you charge them use a setting that is less than 10% of the capacity, 150 ma is about right. When the battery starts to get warm to the touch that means that the capacity is nearly full. A big note is that the voltage will come up quite quickly but the capacity is far from full, that's why your auto charger shuts off. 1.36V to 1.38V per cell indicates full voltage but not full capacity.
__________________
Kip

"If my being here has made your day a little more pleasant then I have done my job" Red Skelton 1913 - 1997 (famous Comedian)
kip51035 is offline   Quick reply to this message.
Old 05-16-2019, 09:52 AM   #10
volksman
RCC Expert Contributor
 
I am: robert j
Join Date: Dec 2002
Location: vernon bridge, pe

Feedback: 5 / 100%
Posts: 862
Total Props: 5
Re: Cycling Nimh batteries

one usefull thing about a cycle under load. it will show voltage vs current. voltage should remain steady no sudden drop as load time increases. gradual voltage decline is what a good pack will have. nicads can be brought back with a cycle to some degree. nimh not. i cycle to make sure its usable to 4.8 volts on a full charge.
volksman is online now   Quick reply to this message.
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the RCCanada - Canada Radio Controlled Hobby Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

Member names may only be composed of alpha-numeric characters. (A-Z and 0-9)

!!ATTENTION ADVERTISERS!! If you intend on advertising anything on this forum, whatsoever, you are required to first contact us here . Additionally, we do NOT allow BUSINESS NAMES unless you are an Authorized Vendor. If you own a business, and want to do sales on this site via posting or private message, you will need to follow the rules. Shops, Stores, Distributors, Group Buys without being authorized will see your account terminated.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Radio of choice?
Which radio is your current favorite to use?
Number of RC Vehicles?
How many boats, cars, planes do you own?

Log-in



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
vBulletin Message

Thread Tools
Display Modes

Forum Jump


All times are GMT -5. The time now is 05:53 AM.


vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.