Search results

Great, so I am speccing the busbar to carry the right kind of current. So can I use the cross sectional area from the powerstream table to correctly gauge the size of my busbars? (as this table is a wire table, I want to check this translates to a rectangular cross section)

I am fusing each cell to internal bus bars, the layout I have in mind is shown here: Each series cell is capable of 88A continuous, but the max load the system I am making would put on the cells is about 51A, and usually significantly lower than this. I would like to build in overheads...

Just a note on this. If you cycle Li-Ion between 90-20% DoD and also (but less important) charge them at lower than 0.5c then they will go thousands of cycles before hitting 80%. LiFePO4 are the cycle life (and safety) king, no doubt about that. But if you can find very cheap Li-Ion and then...

Cheers, just having a look at them, but they look like they are serving a market well beyond myself... You know when you can't find prices anywhere they are probably out of your league!

Yea the Mean Well documentation isn't totally clear about what is programmable and what isn't. But one of the notes for the RCB-1600-48 does say: "8. When charging lead acid battery or battery without BMS, use breaker to disconnect charger and battery after fully charged." Which suggests it is...

Haha, thanks - I was hoping it was just that the vast majority of people here use the generic BMS that don't have these functions, but I was convinced I must have some serious misunderstanding somewhere :P As it happens one of the main Mean Well suppliers in the UKhave just got back to me and...

What you are saying here does not gel with what I am reading in the manual, within the TinyBMS manual is says that: This, to me, reads that there is an internal relay that is able to disconnect the BMS from the charger once the internal conditions are met and only reconnects once the...

Then why in the TinyBMS manual does it say: Thebattery is fully charged, the Charging Done (0x63) event is generated, BMS goes to the Fully Charged state and the SOC value is set to the 100 % value only if all three conditions are met: The voltage of the all cells is at the Fully Charged...

So what is the difference between a "critical value" and "low current"? What is the charger or "charge controller" doing that is different to the BMS?

The BMS I am using - the Tiny BMS - states in it's manual that it monitors charging both by voltage, current and balance. The BMS manual says that it disconnects the charge circuit when the voltage or current conditions are met, and is capable of issuing a variety of error codes should one be...

This is the PSU I'm looking at: https://www.meanwell.com/webapp/product/search.aspx?prod=RSP-750 Output voltage programmable by pot or external voltage and constant current also programmable by external voltage. Then I would rely on the BMS to cut the charge once it reaches the low current...

Yea what was confusing me was that many of the Mean Well power supplies say "constant current, programmable voltage" but their chargers say "constant current, constant voltage". But I guess it just refers to their charge 'profiles'.

So, basically... If a PSU has constant current then it functions in essentially the same way as a CC/CV charger but perhaps lacking things like low current cut off and charge stage led indication?

So I have the basics of how the lithium charge profile works, but I can't quite wrap my head around this last part: What exactly is the difference between a power supply/chargerthat 'switches' to CV mode and a power supply that only has CC mode but has a nominal voltage in line with the...

This is very common for international freight at the moment. I have been shipping a lot of things recently and a 2-3week delay through Europe is common and well over an extra month if shipping from further afield like China on any of the 'normal' shipping services - I have something coming from...

As above, hoping someone has a stock of old/dud cells that I can drain off and use to practice my spot welding before I move on to working on new cells. I'm in Manc/Leeds (I move between the two) in the UK, so around there would be best as I guess posting even dead cells probably gets out...

Upside down and back to front, and then missing a number! 14S9P is what I meant.

A quick bit of CAD I did today, helps me plan everything out and check that it's all set up correctly. This is 8S14P now 14S9P

I am today changing my thinking a bit and now thinking I might go to a 48v system. This should allow me to still feed an inverter, but by reducing it to 29.7Ah I still get the 1.5kWh I was aiming for and I can charge it via a DC-DC buck (this one, over provisioned, capable of 96V20A CCCV). This...

Right, after reading through the TinyBMS manual, it seems like this should work without issue and I also think I understand the whole process a little better. I am going to write out the process as I understand it, which I believe I have correct: 1. Connect battery. PSU/buck supplies 30A...