Possible warning on the PD chargers and Lifepo4 batteries

[saltydawg]

Okay I was reading the other day on diy solar about a guy who has a few lifepo4 batteries deing much faster than they should. He is using the progressive dynamics panel with the lithium charger jumper in place. Someone who knows a lot more than me looked at the specs of the PD charger, and found a problem.

The PD charger is not a smart charger in anyway, even when set for lithium it just keeps trying to charge the battery at the same voltage, meaning its just keeps pumping a float charge in to it.

here is the thread.
https://diysolarforum.com/threads/two-year-old-relion-100-hp-battery-bank-going-south-rapidly.26464/

[Tom&Shelly]

Okay I was reading the other day on diy solar about a guy who has a few lifepo4 batteries deing much faster than they should. He is using the progressive dynamics panel with the lithium charger jumper in place. Someone who knows a lot more than me looked at the specs of the PD charger, and found a problem.

The PD charger is not a smart charger in anyway, even when set for lithium it just keeps trying to charge the battery at the same voltage, meaning its just keeps pumping a float charge in to it.

here is the thread.
https://diysolarforum.com/threads/two-year-old-relion-100-hp-battery-bank-going-south-rapidly.26464/

Well, now I don't feel so bad about missing the boat and buying a PD 4045 before they offered the Lifepo option. Hope I'm not hurting our AGM battery too much since we're charging almost exclusively from shore power while here in the cloudy East.

Thank you for the "heads up" Scott!

Tom

[saltydawg]

Tom your agm likes to be kept fully charged, it should not be a problem.

When I did a system on a little guy for someone, I used a agm and pwm solar charger. The reasons is the agm will be happy long term with the constant charge of the solar.

[cwaet]

Okay I was reading the other day on diy solar about a guy who has a few lifepo4 batteries deing much faster than they should. He is using the progressive dynamics panel with the lithium charger jumper in place. Someone who knows a lot more than me looked at the specs of the PD charger, and found a problem.

The PD charger is not a smart charger in anyway, even when set for lithium it just keeps trying to charge the battery at the same voltage, meaning its just keeps pumping a float charge in to it.

here is the thread.
https://diysolarforum.com/threads/two-year-old-relion-100-hp-battery-bank-going-south-rapidly.26464/

Fascinating, thanks for sharing. I have been using the PD9145ALV for my 200 AH lifepo4 battery bank. I got the PD charger/converter as that is what is sold on the Battleborn website. Am I safe to turn the charger off when stored, charged up, and/or plugged in at home/camp, or should I go with a victron/similar dedicated lifepo4 charger that has multiple stages? Very new to lithium, so feel free to correct me if I am misunderstanding.

[saltydawg]

Fascinating, thanks for sharing. I have been using the PD9215ALV for my 200 AH lifepo4 battery bank. I got the PD charger/converter as that is what is sold on the Battleborn website. Am I safe to turn the charger off when stored, charged up, and/or plugged in at home/camp, or should I go with a victron/similar dedicated lifepo4 charger that has multiple stages? Very new to lithium, so feel free to correct me if I am misunderstanding.

I dont know the PD stuff so I cant say

Personally would buy a better charger then disable how ever the charger in the PD. I like the victron stuff as its blue tooth and can do 100% custom charging settings.

[John61CT]

I have NEVER YET seen a charge source marketed specifically as being "compatible" with LFP

programmed anywhere near to a profile conducive to longevity.

All you need is a charge source designed for lead batts only is fine

with user-custom **adjustable** setpoints, and/or even with a dumb PSU or DC-DC, maybe an adjustable HVC circuit to cut off the charger's source.

If the cells are from a top quality maker and trustworthy seller (a HUGE "if")

the bank can last for decades, 8-10,000 cycles IMO.

But you do need to "coddle" it to get that

stay well away from the top and bottom voltage shoulders,

use 80% or less of theoretical capacity, and

ensure prevention of any "unexpected events" that shorten longevity, some of which can render all those expensive cells instant scrap.

[saltydawg]

First I dont know why I am responding to your reply, besides you are flat out wrong, on multiple points.

I have NEVER YET seen a charge source marketed specifically as being "compatible" with LFP, programmed anywhere near to a profile conducive to longevity.

The victron lifepo4 are perfect for 99% of people, they have the proper voltages, and the proper storage settings etc. Can they be tweeked, sure but all the tweeking does is slow the last 10% of the charge.

All you need is a charge source designed for lead batts only is fine

This is flat out wrong and will ruin batteries, lead acid batteries want a float charge high enough to trickle in a few % of the charge constantly. Lead acid chemistry allows this by making the cell resistance higher as the cell is closer to 100% charge. Doing a long term constant charge on a lifepo4 with a fla charge profile will over charge and ruin the cells.

with user-custom **adjustable** setpoints, and/or even with a dumb PSU or DC-DC, maybe an adjustable HVC circuit to cut off the charger's source.

Again if its as you say "adjustable" set points, at that point its not a charger as much as a psu. why complicate it, just buy a quality lifepo4 charger.

If the cells are from a top quality maker and trustworthy seller (a HUGE "if")

pretty much all makers are quality, and they run quality checks. If they fail those checks they become grade B batteries, and they will still kick LA batteries butts

the bank can last for decades, 8-10,000 cycles IMO.

even the top top makers will claim 5000 cycles and have 80% of the factory capacity. sure at 10k cycles they will still work, but might be at 20% capacity

But you do need to "coddle" it to get that

I guess if you call coddling them charging as they are designed to be

stay well away from the top and bottom voltage shoulders,

use 80% or less of theoretical capacity, and

ensure prevention of any "unexpected events" that shorten longevity, some of which can render all those expensive cells instant scrap.

agreed, except you can charge to 100% but dont leave it there, if your cycling them daily then its not really an issue.