Ian
OffGrid VanDweller
- Joined
- Jan 25, 2020
- Messages
- 63
Aww thanks Will! I have you and this forum to thank for the majority of my knowledge base. I can’t wait to post my setup on show and tell once I’m further along.Nice cell configuration!!
Aww thanks Will! I have you and this forum to thank for the majority of my knowledge base. I can’t wait to post my setup on show and tell once I’m further along.Nice cell configuration!!
That's the one I bought for my BYD batteries on wheels. It's working.I just use this
https://www.amazon.com/gp/product/B07ML2MP9Q.
- Start with the batteries disconnected and set the desired end voltage and the amp knobs turned all the way down.
- Connect the cell(s)
- Turn up the current to whatever rate you want for the constant current.
At this point you need to watch the current, when it gets down to a few hundred mA, the charging is done and you need to take the cell(s) off the power supply. This is the primary difference between the power supply and a true charger. A true charger will either quit charging when the current drops off (preferred) or it will drop the voltage to a float level.
- For assembled solar batteries you will usually hit the power supply limit before you hit the charge limit of the cells.
- If the cells are already charged, you might might not be able to turn the current up very high before the voltage limit prevents it from going higher.
Warning: If you hook it up backwards you can blow out a diode in it. The symptom is that it shows it is pumping current but there is no voltage.That's the one I bought for my BYD batteries on wheels. It's working.
That's the one I bought for my BYD batteries on wheels. It's working.
That is probably the hardest on a PS, of all those things.It is a handy little supply. I use it for all sorts of projects from powering circuit boards to charging batteries to electro-plating bus bars.
From a power point of view, no. I used less than an amp and less than a volt. However, proximity to the Muratic acid was probably not very good for it...That is probably the hardest on a PS, of all those things.
That would probably work just fine for most people. In fact, I am becoming less and less convinced of the need for top balancing if you have a decent BMS. The BMS will balance the cells at the top anyway so after a few cycles you will be at the same place you would have been with a top balance. (Top balancing just gets you there from the beginning)For top balancing without investing in a bench power supply what is the problem with first assembling the cells into the target configuration (12V, 24V, whatever), charging that battery until full and then reconfiguring the cells into a parallel configuration and letting that sit for a day or two? Is that just too slow for people or am I missing something?
Yeah, my cells were pretty well balanced from XUBA. 3x3.279V and 1x3.278V.That would probably work just fine for most people. In fact, I am becoming less and less convinced of the need for top balancing if you have a decent BMS. The BMS will balance the cells at the top anyway so after a few cycles you will be at the same place you would have been with a top balance. (Top balancing just gets you there from the beginning)
Where top ballancing might be important is if you want to do a capacity test of the bank on your first discharge.
It would be interesting to see an accuracy chart for the meters in a PS.Since we talk about settings down to the .01 volt, I find the fine adjustment to be handy (If I am honest with myself, the display is probably not that accurate..... but it still feels right to be able to dial it in.
....snip..
I agree. My setup just has 1 volt and 1 amp knob per channel. It takes a real light touch and a little luck to get the volts set just right.Whether you are using the PS display or a top-end Fluke, being able to fine tune the value is handy..... so I like having the extra knob.
So after days and days of slowly charging my battery bank and getting everything top balanced I was finally able to fully assemble my battery today. The 4 groups of parallel cells all showed either 3.600 or 3.601 prior to making the series connections. I’m still waiting on my bms to arrive prior to doing the final tourqe down and there installing the lock washers. Once connected my meter showed 14.4V. I can’t wait to capacity test the battery after the bms is installed. It feels good to be making progress though.
View attachment 8391
I went with this for $20 less/ has similar specs. Seems good enough to me for lite weight use. https://www.amazon.com/gp/product/B07M9N73YQ/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1I just use this
https://www.amazon.com/gp/product/B07ML2MP9Q.
- Start with the batteries disconnected and set the desired end voltage and the amp knobs turned all the way down.
- Connect the cell(s)
- Turn up the current to whatever rate you want for the constant current.
At this point you need to watch the current, when it gets down to a few hundred mA, the charging is done and you need to take the cell(s) off the power supply. This is the primary difference between the power supply and a true charger. A true charger will either quit charging when the current drops off (preferred) or it will drop the voltage to a float level.
- For assembled solar batteries you will usually hit the power supply limit before you hit the charge limit of the cells.
- If the cells are already charged, you might might not be able to turn the current up very high before the voltage limit prevents it from going higher.
I went with this for $20 less/ has similar specs. Seems good enough to me for lite weight use. https://www.amazon.com/gp/product/B07M9N73YQ/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Any chance you could share with me what you did differently to get your power supply to charge at the full 10a? I’m trying to top balance my 8 280ah cells and it is taking forever!My 4 cell pack of XUBA 280AH starting at 3.298V in parallel.The first 1.5 days I was only pushing 5A because I misunderstood the outputs of my 3 channel power supply. When my mistake was pointed out, it was a "I know that" moment. Thanks to some people here I got that worked out and was pushing the full 10A. Another day at 10A and once it went over 3.4V it started picking up steam and topped out at 3.65V in about 6 hours.
As for the PS meters. They're fine for setting the max amperage output of your PS. For the voltage side, use a good DMM to set the max voltage. Don't trust the voltmeter on the PS, until you have checked it with a DMM. Mine is off by 0.5V on the PS. But it doesn't matter if I set the output with a DMM.
If it is not taking the full 10A, the cells are starting to get charged. However, with 8 cells it could still take a *long* time to complete because even at 10A, you are only pumping 36W.Any chance you could share with me what you did differently to get your power supply to charge at the full 10a? I’m trying to top balance my 8 280ah cells and it is taking forever!
I’ve got it set for constant voltage at 3.6v currently...