Best 48V AC-DC Charger?

[Over9000]

Hello folks,

My LiTime 54V 18A charger is a piece of crap and I need to replace it so I can fully charge up my 48V batteries.

Any recommendations?

 

[pollenface]

I think this 60v 30a bench power supply

https://amzn.asia/d/0Yn6JrI

 

[Backyard]

While a bit expensive. Its hard to beat the chareverter

 

[Over9000]

I think this 60v 30a bench power supply

https://amzn.asia/d/0Yn6JrI

This route wouldn't have intelligent charging.

While a bit expensive. Its hard to beat the chareverter

This is too complex. Looking to keep it simple.

 

[wpns]

This route wouldn't have intelligent charging.

What intelligent charging are you looking for?

This is too complex. Looking to keep it simple.

CV is the canonical 48V charger, but it may be overkill to replace an 18A charger. It’s not intelligent either.

 

[Over9000]

What intelligent charging are you looking for?

CV is the canonical 48V charger, but it may be overkill to replace an 18A charger. It’s not intelligent either.

One that understands the appropriate charging curve for LFPs and tapers off after 80%

 

[jharrell]

One that understands the appropriate charging curve for LFPs and tapers off after 80%

Most LFP chargers are simple 3 stage, CC, CV to absorb then lower float voltage after a time delay, not clear if the LiTime even has float it might just be CC/CV which would be just like that power supply which you just have to remember to shut down and not have any float. At least the power supply you could manually float by dialing down voltage.

Not sure what the 80% taper means, sounds like something from a high power EV charger to maximize C rate well above 1.

 

[pollenface]

This route wouldn't have intelligent charging..

Best chargers i own are bench power supplies and timing switches.

 

[wpns]

Not sure what the 80% taper means, sounds like something from a high power EV charger to maximize C rate well above 1.

I’m not sure either, but it sounds like the normal charge acceptance of an LFP battery is going to drop as you approach full charge.

 

[pollenface]

I believe that's a reference to the "constant current" part

 

[jharrell]

I believe that's a reference to the "constant current" part

That just happens on its own if you have a power supply set to a specific voltage and a certain max current it will go from CC to CV when voltage is hit and current will taper based on battery acceptance.

So a 3 stage charger with float is just a power supply that changes its voltage setting automatically to float sometime after hitting absorb.

 

[Brucey]

Hello folks,

My LiTime 54V 18A charger is a piece of crap and I need to replace it so I can fully charge up my 48V batteries.

Any recommendations?

Looks at meanwell hep series some models can be programmed via canbus to tweak the charge parameters. @hwy17 uses them iirc. Not cheap by any means but silent passively cooled unlike a chargeverter screamer.

 

[Brucey]

Some discussion here: https://diysolarforum.com/threads/psa-chargeverter-is-loud.82677/#post-1072548

 

[hwy17]

Looks at meanwell hep series some models can be programmed via canbus to tweak the charge parameters. @hwy17 uses them iirc. Not cheap by any means but silent passively cooled unlike a chargeverter screamer.

Had my first bug in my HEP-2300-55 this year. Woke up one morning with the power off and dead battery. I control the meanwell with a simple dry contact relay and it was no longer responding to the closed relay by enabling charge. I put the factory jumper back in and it still did not respond. Power cycled it by it's 240VAC grid supply and then it acted normally again and ever since. I'm gonna try to make sure I power cycle it at least once every 3 months now and hope that helps.

Other than that, yeah it's been pumping 24-48kWh/day into my system all winter long. And I nearly made it 1 entire year of 24/7 constant uninterrupted inverter power! Oh well though.

I still have not found it necessary to buy the charge profile programmer tool for my purposes. One voltage setting is good enough for me.

 

[42OhmsPA]

It requires a little work but in the spirit of DIY I'm a huge fan of this
Emerson R48-3000e3 Communication Switching Power Supply Module 48V Induction Heater Power Supply Disassemble With interface

https://a.aliexpress.com/_mPMUpf1

 

[pollenface]

That just happens on its own if you have a power supply set to a specific voltage and a certain max current it will go from CC to CV when voltage is hit and current will taper based on battery acceptance.

That's correct

 

[Over9000]

That's correct

How does that happen? If the power supply outputs constant current, how will it know when to stop? If the battery doesn't have BMS, I fail to see how it would stop accepting current

 

[jharrell]

How does that happen? If the power supply outputs constant current, how will it know when to stop? If the battery doesn't have BMS, I fail to see how it would stop accepting current

Constant current means current is limited to a specified amount, it doesn't mean it "forces" that amount, the batteries will only accept the amount of current based on their IR and the voltage the charger is attempting to attain.

Current flows due to difference in voltage, as the battery charges the voltage rises and less current is accepted, once the charger and battery reach the same voltage no current flows and it is floating.

 

[Over9000]

Constant current means current is limited to a specified amount, it doesn't mean it "forces" that amount, the batteries will only accept the amount of current based on their IR and the voltage the charger is attempting to attain.

Current flows due to difference in voltage, as the battery charges the voltage rises and less current is accepted, once the charger and battery reach the same voltage no current flows and it is floating.

I thought a Power Supply keeps sending a fixed current unless it has the intelligence to "stop" at a certain point.

 

[Wolfpack7483]

It requires a little work but in the spirit of DIY I'm a huge fan of this
Emerson R48-3000e3 Communication Switching Power Supply Module 48V Induction Heater Power Supply Disassemble With interface

https://a.aliexpress.com/_mPMUpf1

I read through the thread on this, and really don't plan/want to use the CAN bus interface. Am I wrong in thinking that all I need in addition to the unit, is wiring and protective devices? I only plan to use it manually @ 120v. I'm guessing this would trip my 1500w generator using propane, if I don't have a way to adjust maximum current.

 

[jharrell]

I thought a Power Supply keeps sending a fixed current unless it has the intelligence to "stop" at a certain point.

That's not how electricity works: https://en.wikipedia.org/wiki/Ohm's_law

 

[Over9000]

I read through the thread on this, and really don't plan/want to use the CAN bus interface. Am I wrong in thinking that all I need in addition to the unit, is wiring and protective devices? I only plan to use it manually @ 120v. I'm guessing this would trip my 1500w generator using propane, if I don't have a way to adjust maximum current.

I'm looking at this unit instead.

Amazon.com

 

[Over9000]

That's not how electricity works: https://en.wikipedia.org/wiki/Ohm's_law

I understand that, but you'd need to set the voltage and current output. That way, it will stop charging once the defined potential us reached. If the voltage us variable and current fixed, it doesn't have a way of stopping barring BMS.

 

[SomethingAppropriate]

I thought a Power Supply keeps sending a fixed current unless it has the intelligence to "stop" at a certain point.

Current is asked for, voltage is given

 

[Over9000]

Current is asked for, voltage is given

Voltage doesn't flow. Current does, rather, it is drawn.