Opus Overheats cells?

B

BoomBoomShroom

New member
Joined
Nov 30, 2017
Messages
23
Hi,

I've been running a few "Charge Test" and i find that during the discharge that some batteries overheat on the Opus. A week later I would run those same cells that overheated, on the Opus, on my IMAX and this would not happen at all. I run both the IMAX and Opus with a current rate of 1.0A. Does anyone else runinto this?
 
I haven't seen any overheat during discharge, only charge and typically bad cells (mostly Sanyos).

A few things to check
- Make sure your Opus fan is running. They have a high failure rate and maybe there's no airflow?
- Check the specsheet for your cells and make sure it's not an older cell where maybe 1A is too much discharge (unlikely but still worth checking)?
- Try the same cell in another Opus and see if results are the same?
 
mike said:
I haven't seen any overheat during discharge, only charge and typically bad cells (mostly Sanyos).

A few things to check
- Make sure your Opus fan is running. They have a high failure rate and maybe there's no airflow?
- Check the specsheet for your cells and make sure it's not an older cell where maybe 1A is too much discharge (unlikely but still worth checking)?
- Try the same cell in another Opus and see if results are the same?
Click to expand...

Thanks for the reply mike.

I have two Opus chargers and the fans cut off at times on both of them, but they usually turn back on. Is that an issue?

I have checked the spreadsheet on the cells (ICR18650-30B) and it can handle a max of 5.8A.

If they aren't heating up during charge, are they still good? I'm going to try both Opus chargers to see their results.
 
The Opus do heat the cells more than the Imax for sure. That can give them what you see. Discharge they should not get that hot and if so its hot around them.

What do you say is hot? Everything below 10c above ambient is ok if you ask me

What it can handle from beginning is not the same as what they can handle as 2nd hand cells.
 
daromer said:
The Opus do heat the cells more than the Imax for sure. That can give them what you see. Discharge they should not get that hot and if so its hot around them.

What do you say is hot? Everything below 10c above ambient is ok if you ask me

What it can handle from beginning is not the same as what they can handle as 2nd hand cells.
Click to expand...

I havent measured the temp with tools, but i would say they were a little below 110F (about 49C). I'm running a test now with the cell so lets see what it reaches. I will make sure to measure the temp properly.

In the end of the day, are these cells safe? They get hot on the Opus but not my IMax or other chargers.
 
Another thing to consider is your ambient temps where the chargers are located. If it's really warm there, and the chargers are working at testing, they generate more heat. When enough is reached the fans kick on to cool the electronics of the charger, not the cell. If things continue to get to toasty, the charger will shut down the discharge until stable temps are reached, then resume afterwards. This is one reason opus can show higher capacity ratings because the cell can have periods of rest.

You could easily run 100 km, if you get a rest every 100 meters ;) But try running it flat out without stopping. Quite different result.
 
Ive run the test and this is what I got.

Ive used my multimeter which comes with a temp feature/attachment. All I had, but still good.

The ambient temp in the room is 19-20c. The cell reached a peek of 30c, but that was in the middle of the cell. At the end, on the negative side, it reached 33c. I dont know which temp to consider as right. One is ok and the other is a little to high.

Would you keep this cell?

Im going to run it one more time on the IMAX in two days and report back.
 
I always run a fan blowing on the cells when charging/discharging on the opus. I have 2 opus and its normal for all cells to get warm/hot I run hundreds of different brands. A fan blowing over the cells will keep them nice and cool. Some people don't want to run an extra fan, but it works.

The only ones that never got hot where 26650 lifepo4 cells ( I ran almost 200 of them. not one got hot), only because they were about 2 feet away from charger in their 26650 holders, they were connected to the opus with 2 feet long wires. That might be a project to try on on the opus put18650 in holders seperate from the charger and see if they will keep cool. That might be why they don't get hot on the IMAX.

The opus has the discharge resisters right under the cells when discharging, that little fan won't remove all the heat especially if your discharging 4 cells. All the heat moves upwards right onto the cells. Even my powertool cells which can handle 20 amp discharge will get warm.

The red sanyos get hot during charging, but that normal for them and I still use them. On battery packs I built, I never notice them getting warm or hot. I only notice on the opus.
 
Maybe it's the cells 1st time charge, eg where the chemistry in the cell hasn't been used in a while & has higher internal resistance = heating, but then after a cycle or two they stabilize & behave normally?
 
BoomBoomShroom said:
Ive run the test and this is what I got.

Ive used my multimeter which comes with a temp feature/attachment. All I had, but still good.

The ambient temp in the room is 19-20c. The cell reached a peek of 30c, but that was in the middle of the cell. At the end, on the negative side, it reached 33c. I dont know which temp to consider as right. One is ok and the other is a little to high.

Would you keep this cell?

Im going to run it one more time on the IMAX in two days and report back.
Click to expand...

It may be the cell, but imho you cannot decide atm.
I have seen that the air coming from the fan, due to cool the elctronics, comes partially up through the slots of the sliders and heats the cells. Right side was worse than left in my case. No clue if this is similar for everyone.
After fanupdate the same cell which was 50 C came out with 24 C, on 20 C ambient.

I found this by chance, when i tested an "obviously" hot cell coming from the right side several times on - by chance - different slots, and realized its only hottest on the right side.
 
Interestingly enough, the cell did not get hot with the IMax at all.

From @Cherry67's comment on the right side is worse than the left, its the same for me. The side with the fan (Right) gets really hot for me. I've noticed the cells I place on the left don't get as hot. The last run I was running a charge test on 4 cells and found the two rightmost cells would reach 33c during discharge, with the ambient temp being 21c, and the left side would sit at around 27c. The whole Opus charger would get hot. I picked it up while it was discharging and it was hotter than the cells themselves. During the charging phase, it would stay at around 23-25c, which is not far off from the ambient temp (21c). I would start the charge test at around 3.4-3.7v, so if it was gonna heat up it would have.

I'm probably going to place a fan or two on the charger so it can cool down a bit and not affect my tests.
 
Part of the problem with the opus is the heat generated from discharge is really close to the cell there fore it heats up. I have added a fan on the back of mine to cool the Dissipative parts and keep the cells cooler
 
jdeadman said:
Part of the problem with the opus is the heat generated from discharge is really close to the cell there fore it heats up. I have added a fan on the back of mine to cool the Dissipative parts and keep the cells cooler
Click to expand...

Pictures of mine are in my harvesting thread.
 
BoomBoomShroom said:
Cherry67 said:
Pictures of mine are in my harvesting thread.
Click to expand...

Hi Cherry67,

mind sharing a link to make it easier for other users in the future to find it.

Thanks :D
Click to expand...

Ahhh... i just just heve been definitely advised by the mods to improve my searching skills, after i made some suggestions about creating a TOT section... and now that :D .
Ok, I made it my life task to find my own thread, not by memory, but by searching..... in the end the successful search word was "(done)".
Heavens and hell, how can somebody else guess that when he wants to find pictures of my Opus fan stand ? :shy:
But in the end, the mods where right - just a bit creativity, and you find everything. :D :D
And here goes the result:

https://secondlifestorage.com/t-2nd-harvesting-campaign?highlight=(done)
 
You must log in or register to reply here.
Back
Top