Barbar0ssa
New Member
- Joined
- Mar 3, 2021
- Messages
- 80
I am definitely a newbie. Right now they are in parallel and the cases are positive on these cells. Do you see a risk in this current resurrection attempt?Maybe owners of these batteries should reconsider the container they use to build or store in since there is reported v leakage to the case. some cases are the negative terminal,
A plastic tub as in op's photo, even with drainage holes, may provide a current path across batteries in series at any sign of moisture.
It just looks like a accident waiting to happen holding these batteries, series connected across the top, when they are sitting in water proof containers. If not a total short, may cause the BMS to behave erratically if water gets in and covers the base.How should I contain them?
I use clips for my battery sense terminals but all it is drawing is 16 mA so no big deal. I think as long as the OP is monitoring the current the connection will be OK, but....clips can slip and where they go when they slip could be a problem, so you ain't wrong. I admit when I was doing testing I was having to move things around a lot and it was easier to use clips, but once I settled on a configuration, from there it was heavy gauge and torque those connections down. Sometimes you have to be a bit of a gun slinger and get the job done.Ugh - ditch those clip leads. Make proper connectors, even for something as simple as this.
You are doing fine, taking it nice & easy, from your update they seem to be behaving. There is no chemical leakage or anything and very little to worry about at this stage.I am definitely a newbie. Right now they are in parallel and the cases are positive on these cells. Do you see a risk in this current resurrection attempt?
How should I contain them?
Do you have any suggestions of what to use in place of those clips? Only asking because I am waiting for this very power supply to arrive.You really want to change those leads. Put on proper gauge wire and ring terminals.
Do you have any suggestions of what to use in place of those clips? Only asking because I am waiting for this very power supply to arrive.
You really want to change those leads. Put on proper gauge wire and ring terminals.
While I am running 15w the wire gauge should be ok (I think) but you are right I will put on rings. Parts on order.
It's not just about the wattage or amperage running through the cable. Those clips add a point of high resistance, and can mess up the voltage reading inside of the power supply, causing your cells to over, or under, charge.While I am running 15w the wire gauge should be ok (I think) but you are right I will put on rings. Parts on order.
My power supply tapers off as it gets towards 3.6v. I leave mine on the full 10 amps (actually I leave it on 9a, so I'm not maxing out the power supply) and by the time it's almost charged it's down to 1-2a.Well, I made some 12 awg leads with ring terminals and it made quite a difference without changing anything else!
Before:
View attachment 64835
After: View attachment 64836
Looks like 3.6 days to charge the remaining 80% at this rate. Should I keep charging at 10 amps or should I decrease the current setting?
It probably won't be popular here, but I think I should throw this out: The quality of the leads and the ring terminals vs. alligator clips can make a difference, but not much and not the way most people think.My power supply tapers off as it gets towards 3.6v. I leave mine on the full 10 amps (actually I leave it on 9a, so I'm not maxing out the power supply) and by the time it's almost charged it's down to 1-2a.
I agree with pretty much all of that .... but would add that one of the things that causes the cells to be damaged during top balance is loss of patience .... so lets crank up the voltage on the power supply a little to speed things up.It probably won't be popular here, but I think I should throw this out: The quality of the leads and the ring terminals vs. alligator clips can make a difference, but not much and not the way most people think.
If you think about it, you have your charge source set to the right voltage, and you connect it to your cells. No matter how good the connection is or how good the wires are, there will be some resistance in the wire and therefore some voltage drop between your charge source and the cells. Ok, fine.
As time goes by, the difference between the voltage of the charge source and the voltage of the cells goes down. By definition (ohm's law) the current between the two goes down. Eventually the cells and the charge source are at the same voltage, so there is no current between the two, so there is no voltage drop on the wire. That means that the cells are charged to what you have the charge source set to, no matter how tiny the wires are that connect them.
So, what does using really good ring terminals and really big wire do for you? It allows the process to go a bit faster. Does it make the end result any better? Absolutely not.
This discussion (about charging your cells initially) is not at all related to how you deploy your cells to an operational system. It is critical that the connections and wire be appropriate to minimize the losses in your system. Different situation, different answer.
I agree with pretty much all of that .... but would add that one of the things that causes the cells to be damaged during top balance is loss of patience .... so lets crank up the voltage on the power supply a little to speed things up.It probably won't be popular here, but I think I should throw this out: The quality of the leads and the ring terminals vs. alligator clips can make a difference, but not much and not the way most people think.
If you think about it, you have your charge source set to the right voltage, and you connect it to your cells. No matter how good the connection is or how good the wires are, there will be some resistance in the wire and therefore some voltage drop between your charge source and the cells. Ok, fine.
As time goes by, the difference between the voltage of the charge source and the voltage of the cells goes down. By definition (ohm's law) the current between the two goes down. Eventually the cells and the charge source are at the same voltage, so there is no current between the two, so there is no voltage drop on the wire. That means that the cells are charged to what you have the charge source set to, no matter how tiny the wires are that connect them.
So, what does using really good ring terminals and really big wire do for you? It allows the process to go a bit faster. Does it make the end result any better? Absolutely not.
This discussion (about charging your cells initially) is not at all related to how you deploy your cells to an operational system. It is critical that the connections and wire be appropriate to minimize the losses in your system. Different situation, different answer.
Yep. Not understanding can lead to not good results. Agree with you completely @Bob B. However, understanding can make it so the intermediate and final results make sense to you. Ohms law is your friend.I agree with pretty much all of that .... but would add that one of the things that causes the cells to be damaged during top balance is loss of patience .... so lets crank up the voltage on the power supply a little to speed things up.
The other thing is .... hey, I'm not getting anywhere near as much current as I should be .... so, lets crank up the voltage a little to get more current.
So ..... the crappy leads can definitely affect the outcome.
I was having problems with getting the current I should be from my power supply .... replacing the crappy alligator clips pretty much doubled my current.