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Backup Generator Charging LifePo4

JIMMY

Solar Journeyman
Joined
Sep 24, 2019
Messages
79
Location
Queensland Australia
Hi all,

I recently purchased an off grid property off an aging gentleman who can't get out there anymore.

Some information is sparse.

I plan to replace the aging 45kwh lead acid off grid solar battery bank to a 30-35kwh 16s LifePo4 battery bank, increase the solar (currently 4500w of panels) and get the place 100% solar powered.

The current owner has not been shy on power usage. He still runs incandescent bulbs throughout including some 250w spotlights!

Primarily it's charged by a Outback FM80 -150 Solar charge controller.

The Inverter is a Latronics unit that does not offer charging.

The existing backup generator is an old Lister diesel and charges the existing batteries with a Stanbury 50amp constant voltage charger at 54.72v or 56.88v.

The backup generator auto starts when batteries drop to 48v and charges the batteries.

My question is could I use this charger in a pinch to charge the lifepo4 batteries?

I don't want to charge them to full but more put a bit of charge back in them until the sun comes out as an emergency backup?

Tia

Jimmy
 
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Hi Will , I gotta show you the battery I bought from China, I've been testing it all weekend , it's a 500 amp hr Lithium commercial grade unit with handles and a charger, the charger failed today though, it has a BMS , its in a stainless case with lifting handles .its cool man.20191024_202148.jpg
 
Hi Will , I gotta show you the battery I bought from China, I've been testing it all weekend , it's a 500 amp hr Lithium commercial grade unit with handles and a charger, the charger failed today though, it has a BMS , its in a stainless case with lifting handles .its cool man.View attachment 1482
Link to battery??
 
Hi Will , I gotta show you the battery I bought from China, I've been testing it all weekend , it's a 500 amp hr Lithium commercial grade unit with handles and a charger, the charger failed today though, it has a BMS , its in a stainless case with lifting handles .its cool man.View attachment 1482

I'm blown away by the cables. Did you find specs on those?

Through clicking seller, found 24V version. Entertaining answers to questions, as well:

1574396677648.png
 
Yeah, it should read 2pcs of 48v in parallel to get 48v at 200ah. In series, you would end up with 96v at 100ah. You got to keep an eye on these Chinese; many folks are having bad experiences trying to save a buck or two on this crap without putting some real thought into the long term but to each his own.

My issues with these batteries are first, what is the warranty, and second is the 2000 cycles. I looked long and hard at this issue, and by my figures, in the long run, one is better off buying Battleborn. There is no doubt about quality, performance, and warranty.
 
We have an extended thread going on these ShunBin batteries, you may find it enlightening.
Couple of us bought 24V/400AH packs and are tearing into them and other info there too.

 
I just came across this thread through my searching on this site.

Is it possible to charge 4 LiFePO4 batteries (12V 100a) with my Honda 2000i generator?

I want to do solar, but the lack of sun on our property is an issue.
I even have a "small" river feeding the pond on the property, but the flow is to little to use micro-hydro electric.
Also considering wind as well.

In the meantime, I want to be able to have power with only using the generator once in a while to charge a battery bank.
Probablly charge for a few hours during the day and batteries the rest of the time.

Is this possible? If so, how long do you think it would take to charge the battery bank?
https://hondanews.com/en-US/power-e...iet-series-generator-technical-specifications

Thanks!
 
Yes, with an appropriate Constant Current Constant Voltage charger. Your limitation is that the EU2000 actually only delivers 1750W "normal" which is 15A, so keeping the charger below 120V/1500W won't stress the little genny.

There are many chargers, and even good cheap imported ones that work well. BUT if you are the slightest bit picky and cautious, I'd suggest looking at these two companies and these products as a consideration. These are Adjustable & Variable Volts/Amps which will allow you to also top balance the cells and more.

100AH LFP can take 0.5C/50A charge rate nicely (that's top amps recommended), go with 30A to 50A capable Powersupply. The 50A units will get close to 1200-1400W pull from the genny.

TekPower TP1540E DC Adjustable Switching Power Supply 15V 40A Digital Display

Products found matching '15v'. - Volteq - Reliable Regulated Variable DC Power Supplies
 
Yes, with an appropriate Constant Current Constant Voltage charger. Your limitation is that the EU2000 actually only delivers 1750W "normal" which is 15A, so keeping the charger below 120V/1500W won't stress the little genny.

There are many chargers, and even good cheap imported ones that work well. BUT if you are the slightest bit picky and cautious, I'd suggest looking at these two companies and these products as a consideration. These are Adjustable & Variable Volts/Amps which will allow you to also top balance the cells and more.

100AH LFP can take 0.5C/50A charge rate nicely (that's top amps recommended), go with 30A to 50A capable Powersupply. The 50A units will get close to 1200-1400W pull from the genny.

TekPower TP1540E DC Adjustable Switching Power Supply 15V 40A Digital Display

Products found matching '15v'. - Volteq - Reliable Regulated Variable DC Power Supplies
That sounds great! Thanks for the help.
 
Is it possible to charge 4 LiFePO4 batteries (12V 100a) with my Honda 2000i generator?

Thanks!
Another options that is more DIY route is to modifiy some server power supplies to output DC in the correct range. You can feed that directly to a BMS that is going to monitor cell voltage or into a MPPT SCC in which case the DC input looks just like solar panels.

See the link in my sig for PSU mods.
 
I’m trying to build my first system and have a question I can’t find the answer to. I have a Yamaha 2000 inverter generator but I also have a No-name 5000w non-inverter generator. Can I use the non-inverter generator (larger gas tank) to power my LiFePO4 enabled charger? I’m guessing it depends on how well the charger handles the “dirty” AC output from the generator and therefore how stable the DC output from the charger is.

Doing the math, it may be irrelevant. My charger can output 50 amps at 24VDC (1200w). Even at 100% efficiency that is less than the output of the Yamaha (1800w = 15 amp at 120VAC).
 
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