Am I killing my Lipos? - RCCanada - Canada Radio Controlled Hobby Forum
RCCanada - Canada's Radio Control Hobby Forum
Electronics Discuss radios, chargers, etc...

Closed Thread
Thread Tools Display Modes
Old 04-18-2008, 06:14 PM   #1
RCC Senior Contributor
thuebner's Avatar
I am: Travis H
Join Date: Mar 2007
Location: Muenster, Saskatchewan

Feedback: 9 / 100%
Posts: 590
Total Props: 13
Am I killing my Lipos?

       Remove this ad - become a site supporter!
I am wondering what is the rule of thumb when it comes to running lipos? I am usng E-flite 7.4v 800mah lipo's in my Blade CX2. I stop flying and change packs when I notice a loss in power. If it takes more throtle to maintain a hover or does not lift as quickly I land as soon as possible. Is this an acceptable way of judjing a packs voltage/capacity or should I be landing before a power decrease is noticed? I am noticing a decrease in performance of the two packs that I have been using in this manner. The packs are only about four months old, but have quite a few flights on them. This leads to the question, am I killing my Lipos?
I normally charge the packs with the supplied balancing charger, but I have checked the mah replaced after a flight with my Accuclcle Elite charger.
Here is an example of the two packs before and after a flight.
Pack "A" - After a complete charge I get a reading of 8.34V.
After a flight a reading of 7.31V.
After charging with the Accucycle 8.37V and replaced 661mah.

Pack "B"- After a complete charge 8.82V.
After flight 7.5V.
After charging 8.83V, replaced 523mah.

I need to figure out how to properly use lipos without damaging them before I can move onto bigger projects.
Thanks in advance for any advice offered.

Pie tastes better with Cool Whip.
thuebner is offline   Quick reply to this message.

Sponsored Links - Subscribe to remove this ad.
Old 04-18-2008, 06:34 PM   #2
I am: Boolean21
Join Date: Sep 2002
Location: Singapore

Feedback: 0 / 0%
Posts: 38,228
Total Props: 56
Re: Am I killing my Lipos?

To get the most out of a lipo the following should apply,

minimum open circuit resting voltage after pack has cooled = 3.7 v/cell
maximum 80% of capacity discharged.
No more than 60C temperature
Try to avoid dropping the pack below 3.2-3.3 v/cell under load in flight, to check this you need a micrologger or equivalent way of monitoring pack voltage real time in flight.

As you use the pack and it ages you have to discharge it less to meet the 80% rule, this is where measuring the voltage after a flight becomes important.

If you follow the above you are not abusing your packs, and a decent pack should give you at least 100-200 cycles before you lose 20% of its capacity. If you can't get this out of them, the pack has crappy cells. There are high quality low cost packs, and low quality high cost packs! Choose wisely!

Lipos also have a shelf life, don't buy them if they are going to sit. Try and cycle them out before winter hits so they don't sit and you will get more time out of them.

On my big 10s packs (10s 5000 mah), after the second season of flying (going into a third year) they pretty much fail regardless of how many cycles I have on them.
PurgatorY is offline   Quick reply to this message.
Closed Thread

Quick Reply

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:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Your Name
Your first name and last initial is required if you plan on using the forum.
Which city & province you live in. This is mandatory for classified listings.
Radio of choice?
Which radio is your current favorite to use?
Number of RC Vehicles?
How many boats, cars, planes do you own?


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

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 05:18 PM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2016 DragonByte Technologies Ltd.