RC-Monster Forums  

Go Back   RC-Monster Forums > RC-Monster Area > General Discussion

Reply
 
Thread Tools Rate Thread Display Modes
Eagle Tree reading below 5V
Old
  (#1)
J57ltr
RC-Monster Aluminum
 
Offline
Posts: 610
Join Date: Feb 2009
Location: Tomball/ Houston Tx.
Eagle Tree reading below 5V - 01.15.2011, 12:00 AM

So I have 15 18650 cells and I was making a 3S5P power source. I noticed that the output should have been at least 6Ah, but I would only get about 3.5Ah. I ended up taking all the cells apart to match them. I decided that I would use my Eagle tree in series with my charger and battery and just log the info on my computer. I know it doesn't work below 5V but if I am in live mode monitring it has anyone tried this?

Jeff


The Warnings & Cautions discussed in this manual cant cover all possible conditions/situations. It must be understood that common sense and caution are factors which cant be built into this product.
   
Reply With Quote
Old
  (#2)
What's_nitro?
Soldermaster Extraordinaire
 
What's_nitro?'s Avatar
 
Offline
Posts: 4,529
Join Date: Apr 2007
Location: Plymouth, MA, USA
01.15.2011, 12:27 AM

What was the cut-off set to during your discharge? You're only taking 700mAH from each cell, which I am assuming is rated for 1.1AH.

Sorry I don't know anything about Eagle Tree stuff........

Last edited by What's_nitro?; 01.15.2011 at 12:46 AM.
   
Reply With Quote
Old
  (#3)
J57ltr
RC-Monster Aluminum
 
Offline
Posts: 610
Join Date: Feb 2009
Location: Tomball/ Houston Tx.
01.15.2011, 01:05 AM

They are 2200 mah cells and there are 5 in parallel, for a total of 11 ah. Figuring that the cells are pretty well used I am going to shoot for a more realistic 1.6 ah for each cell and 8 ah.

I took them apart and had a single cell that shot up to 5 volts and when you measure it with a DMM the voltage drops, so I found my bad cell.

The cutoff was set for 3.0V per cell.

Jeff

edit: The other thing was that the other 2 5p cells were getting about 5200mah at a 5 amp discharge. The other 5p cell, the voltage would increase a lot faster during charging and it would drop faster during discharge.


The Warnings & Cautions discussed in this manual cant cover all possible conditions/situations. It must be understood that common sense and caution are factors which cant be built into this product.

Last edited by J57ltr; 01.15.2011 at 01:08 AM.
   
Reply With Quote
Old
  (#4)
What's_nitro?
Soldermaster Extraordinaire
 
What's_nitro?'s Avatar
 
Offline
Posts: 4,529
Join Date: Apr 2007
Location: Plymouth, MA, USA
01.15.2011, 01:15 AM

Oh, OK. There was a bad cell after all... I had no idea they made the 18650's in 2200mAh. So then why are A123 26650s only 2300mAH? I feel robbed...
   
Reply With Quote
Old
  (#5)
J57ltr
RC-Monster Aluminum
 
Offline
Posts: 610
Join Date: Feb 2009
Location: Tomball/ Houston Tx.
01.15.2011, 01:26 AM

They actually make the 18650's in lots of flavors. There are several different makers. Most of the ones I am seeing are in the 2000-2600mah range. These aren't like the A123's most are between .8C-2C discharge rate, but they are good for some some stuff I have been using them for. Cheap cordless drills, flashlights, and this one is for a 12V power source for a 50W inverter and 12V plug. It had a 12V 4ah battery in it, but it died a long time ago.

Jeff


The Warnings & Cautions discussed in this manual cant cover all possible conditions/situations. It must be understood that common sense and caution are factors which cant be built into this product.
   
Reply With Quote
Old
  (#6)
J57ltr
RC-Monster Aluminum
 
Offline
Posts: 610
Join Date: Feb 2009
Location: Tomball/ Houston Tx.
01.15.2011, 06:53 PM

I got it to work a few times. but the charger kept faulting out saying the battery was not connected, and I would see open circuit voltage around 22V. Not real sure if it was a connection or not.

Jeff


The Warnings & Cautions discussed in this manual cant cover all possible conditions/situations. It must be understood that common sense and caution are factors which cant be built into this product.
   
Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump







Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2025, vBulletin Solutions Inc.
vBulletin Skin developed by: vBStyles.com