Best 48 Volt Battery Charger for EG4/GYLL 48 volt battery

[Solar Newbee]

What is the best 48 Volt Battery Charger for EG4/GYLL 48 volt battery? Is it best to purchase the 48 volt battery charger from Signature Solar or are there other 48 volt chargers that will work with the EG4/GYLL 48 volt batteries? Thanks

 

[John Frum]

What is the best 48 Volt Battery Charger for EG4/GYLL 48 volt battery?

Generally speaking the best battery charger is an inverter/charger.
For example https://www.victronenergy.com/upload/documents/Datasheet-MultiPlus-II-48V-3kVA-35-50-120V-EN.pdf

Is it best to purchase the 48 volt battery charger from Signature Solar or are there other 48 volt chargers that will work with the EG4/GYLL 48 volt batteries?

Not necessary.

An inverter/charger is actually an inverter, ac2dc charger and an automatic transfer switch.

 

[OffGridInTheCity]

If you want just 'plain' chargers at reasonable $ but higher amps - I've had good luck with YZPOWER chargers / solid and can be tweaked. For example - here's a lifepo4 16s 48v @ 15a = 720w. https://www.ebay.com/itm/283842661014?hash=item4216574a96:g:6G4AAOSwrWBd6hN5 Search ebay "YZPOWER 48v Charger" for a wider listing.

I have 4 of them in parallel for 3000w of charging. By having several I can choose the load on my generator in 800w increments. Not pushing them - just sharing

I also have AIMs inverters - but they can't act as a charger and inverter at the same time. So maybe check this out if you buy a charger/inverter.

 

[SignatureSolarUS]

we have a 33% discount on the chargers if you buy during a battery purchase, call in to buy a charger and the sales team will honor it in on the back end

 

[Solar Newbee]

I have 2 MPP Solar 5048 inverter/charger, but I don't have them setup and running yet, and won't for some time. So for now, I'd like to keep my five 48 volt 100Ah EG4/GYLL batteries charged every now and then to keep ready for when I get my Solar system installed. Just looking for a 48 volt charger that will work and is fairly priced. Thank you.

 

[ArkRob]

we have a 33% discount on the chargers if you buy during a battery purchase, call in to buy a charger and the sales team will honor it in on the back end

Are these rated for continuous use that would be seen in bad weather?

E.G. - would these be able to keep a bank charged (possibly multiple paralleled) if there were a 5-10 days of cloudy/rainy weather?

 

[Solar Newbee]

OffGridInTheCity- Thank you for your information. Question do you have the EG4 48 volt batteries from Signature Solar and are you using the YZPOWER 48v Charger on those batteries with no issues?​

 

[OffGridInTheCity]

OffGridInTheCity- Thank you for your information. Question do you have the EG4 48 volt batteries from Signature Solar and are you using the YZPOWER 48v Charger on those batteries with no issues?​

I use the 14s model on my 14s100p 18650 lithium-ion powerwall - no issues / work fine. They have aluminum cases with ridges for heat distribution as they get warm so it's best to have a place for them with a little air-flow.

You would want the 16s model as I believe EG4(s) are 16s LifePo4. Check your specs as 16s should be a max voltage of 58.4v. They are full chargers - CC/CV charging. You can open them and adjust the voltage a bit if you wanted to be <100%, say 58v max charge to 'precisely match' the spec sheet from here - https://cdn.shopify.com/s/files/1/0559/2147/5789/files/48V100AH_LCD_SPEC.pdf?v=1631566461
Note: It could be the BMS cuts off at 58v? as 58.4v is the general max for 16s LifePo4.



If you look at the charger they suggest you buy ( https://www.signaturesolar.us/products/48v-25a-120v-battery-charger-by-eg4 ) notice the spec is 16s LifePo4 - 58.4v max, same as YZPOWER 16s LifePo4 charger

 

[twhouse1]

Generally speaking the best battery charger is an inverter/charger.
For example https://www.victronenergy.com/upload/documents/Datasheet-MultiPlus-II-48V-3kVA-35-50-120V-EN.pdf

Not necessary.

An inverter/charger is actually an inverter, ac2dc charger and an automatic transfer switch.

I am building out an EG4 48v batt bank, and I am close to purchasing 2 Victron MultiplusII 48/3000/120v units that will work together for 120/240. Looking at Victron's "Manual-connecting-other-lithium-battery-systems-to-Multis-and-Quattros-EN.pdf" they talk about their "assistant" software and wiring that has a temp sense feedback and "allow to charge" which I am assuming means "charge under this voltage." EG4 bms has voltage and temp and some jacks on the front of the pack for communication. If the charge parameters in the Multi are set to not exceed the pack voltage and temp sensors, seems like the MultiplusII will stop charging. BMS is in charge; Multi doesn't add when params are met.

I am adding a couple of Victron Solar Chargers that will directly charge the battery pack during the day. They also would be set to charge based on the battery specs. The Mulit's Charger would be used from grid AC in cases where solar is inadequate to keep the bank charged; and/or of grid down a generator will be used.

BMS will stop the charging anyway based on its settings...

Does anyone have concerns about this design? Anything I missed?

Many thanks!

 

[John Frum]

I am building out an EG4 48v batt bank, and I am close to purchasing 2 Victron MultiplusII 48/3000/120v units that will work together for 120/240. Looking at Victron's "Manual-connecting-other-lithium-battery-systems-to-Multis-and-Quattros-EN.pdf" they talk about their "assistant" software and wiring that has a temp sense feedback and "allow to charge" which I am assuming means "charge under this voltage." EG4 bms has voltage and temp and some jacks on the front of the pack for communication. If the charge parameters in the Multi are set to not exceed the pack voltage and temp sensors, seems like the MultiplusII will stop charging. BMS is in charge; Multi doesn't add when params are met.

I am adding a couple of Victron Solar Chargers that will directly charge the battery pack during the day. They also would be set to charge based on the battery specs. The Mulit's Charger would be used from grid AC in cases where solar is inadequate to keep the bank charged; and/or of grid down a generator will be used.

BMS will stop the charging anyway based on its settings...

Does anyone have concerns about this design? Anything I missed?

Many thanks!

LFP batteries don't need temperature compensation for charging.
A commodity FET based BMS should never trip during normal operation.
The charge sources should be configured to work within the safe envelope for LFP batteries.

 

[Samsonite801]

One of the guys here liked this one (can search for the thread), as he indicated it has a fairly high efficiency rating (93%):

This product is no longer available.

This product is no longer available.

www.alibaba.com

Here's the other thread, it was Lt.Dan:

48v Battery Charger?

Hey guys, I'm looking for a backup battery charger for my RV, and I've run into atleast 1 problem with every charger I find! AIMS 48v Charger is nice, especially with variable amperage output, but it has a terrible 80% efficiency, and is only 18.75a output, for $300! I also don't know what the...

diysolarforum.com

 

[offgriddave]

the signature solar charger is only 800-900w

EDIT:

But I just got delivery confirmation for my 220v HP ESP120 power supply which requires to be opened and adjusted to 53.8V max
Unknown if it is CC/CV constant current constant voltage at max. My EE friend says it won't work but he's been wrong (a lot, he owes me because of this)

anyway I bought this ESP120 on EBAY and will go pick it up tomorrow and wire it up to my 240v single phase generator sometime this week

 

[twhouse1]

LFP batteries don't need temperature compensation for charging.
A commodity FET based BMS should never trip during normal operation.
The charge sources should be configured to work within the safe envelope for LFP batteries.

Re: temp: I think I was thinking that parameter was related to not charging when the battery is below a certain temp.. Agree with your comments. Thanks SJ!

 

[John Frum]

Re: temp: I think I was thinking that parameter was related to not charging when the battery is below a certain temp.. Agree with your comments. Thanks SJ!

If your battery will ever experience temperatures approaching 0 Celsius the your BMS should support low temperature charge disconnect.

 

[Stinger]

If you want just 'plain' chargers at reasonable $ but higher amps - I've had good luck with YZPOWER chargers / solid and can be tweaked. For example - here's a lifepo4 16s 48v @ 15a = 720w. https://www.ebay.com/itm/283842661014?hash=item4216574a96:g:6G4AAOSwrWBd6hN5 Search ebay "YZPOWER 48v Charger" for a wider listing.

I have 4 of them in parallel for 3000w of charging. By having several I can choose the load on my generator in 800w increments. Not pushing them - just sharing

I also have AIMs inverters - but they can't act as a charger and inverter at the same time. So maybe check this out if you buy a charger/inverter.

Do you manually connect the charger leads or are they permanently fixed to the buss/battery. I'm asking because the instructions on my 2 units says the charger need to be on before connection to battery. I'm wanting a more automatic function - AIO uses the generator contacts to start the generator when battery is at 25% and would open the contacts when battery reaches desired voltage... maybe 55%

 

[OffGridInTheCity]

Do you manually connect the charger leads or are they permanently fixed to the buss/battery.

The chargers (120v -> 48v) are connected all the time. When I hook the generator to the 120v circuit - they come on and start charging

I'm asking because the instructions on my 2 units says the charger need to be on before connection to battery.

This doesn't make sense to me as the type of chargers I'm thinking of are really simple devices - e.g. power in/charging current out..

I'm wanting a more automatic function - AIO uses the generator contacts to start the generator when battery is at 25% and would open the contacts when battery reaches desired voltage... maybe 55%

I manually stop the generator when I'm happy with the amount of charge.

 

[Stinger]

The chargers (120v -> 48v) are connected all the time. When I hook the generator to the 120v circuit - they come on and start charging

Its cool that yours is fixed and gives me more confidence to follow suit

This doesn't make sense to me as the type of chargers I'm thinking of are really simple devices - e.g. power in/charging current out..

Probably cover their A statement? I saw it as maybe backfeed protection?

I manually stop the generator when I'm happy with the amount of charge.

I will more than likely do this as well... so, you/I fire up the generator and it outputs 120vac to the battery charger with fixed dc leads to battery and when i'm satisfied with the battery charge, just turn off generator. Thanks BTW my ac/dc chargers are sunpay

 

[offgriddave]

Don't forget... when you are sizing

generators are more fuel efficent if they are at near 100% load (except inverter generators), so you want to match your generator's 100% output to the charge output. Up to 35% more effiecent. If you're paying $3 for propane or $6.90 for gas (like me!), that's a buttload of money.

One more thing. You have to consider this: the ineffiency of the charger. Between 25-20% gone, so add that. Ignore the 95% claims they're lies.

My generator (at propane) max output: 3300

(warning back of the napkin math, you could probably nitpick)

75% of that: 2475 (due to 25% loss in ineffiency, guess here, making the worst case scenario)
2475 / 55v (55v is the average it's going to spend most of its time from my experience)
2475 / 55 = 45 amps.

The chargers amps are rated at their maximum volts (58v) .. so you 're going to have to calculate tthat down to 55... so a "20 amp" 58v charger is actually ... 58v*20a=1160w. 1160w/55v=21amps ... 21 amps at 55v.

match that to my generator (45amp) I need two 21 amp chargers (42a) to get close enough to 45a

The 35% fuel efficency difference betweed 100 gallons of propane/gas:

35% less of 100 gallons of propane at $3, $300 propane is now $195. Saving $105 bucks!
35% less of 100 gallons of non-ethanol at $6.90 gallon, $690.. is now $448. Saving $242 bucks!!!!

so it is actually cheaper to buy more chargers than paying for fuel.

don't buy the signature solar chargr they mislead everyone on the specs from the beginning to make a quick buck.

 

[Stinger]

WOW, thank you... My setup is 3500 peak/3000 continuous Predator Inverter Charger (already had for RV travel), 58.4V 20A Lifepo4 Battery Charger for 16S (48V) 51.2V Lifepo4 Battery Power Tool, sooo I'm close to what you described above... Right?

 

[offgriddave]

WOW, thank you... My setup is 3500 pear/3000 continuous Predator Inverter Charger (already had for RV travel), 58.4V 20A Lifepo4 Battery Charger for 16S (48V) 51.2V Lifepo4 Battery Power Tool, sooo I'm close to what you described above... Right?

Sorry, since you have an inverter generator, my calculation's don't apply. They are more effiecent and don't need to take this inconsideration.

I don't know what the effiency gain is on inverter generators? A lot better?

I tried to google it but it was blog spam. Nobody actually tested the numbers. Heres where I got the 35% non-inverter generator numbers (and I can back it from experience)