Can I Charge My LiFeP04 Battery With a Lead Acid Charger?

[howson]

howson Howard,

Thank you for sharing the BMPRO sites. It looks like the Aussies have a good grip on Lithium batteries and chargers. Here is a video that illustrates what I have been attempting to convey about battery DOD with a lead acid charger. I was also surprised to see their battery monitoring system uses SOC as well as SOH (state of health) which we have used in the auto industry for quite a while. Also accurate info on the use of DCDC converters and something that has not been discussed here is variable output alternators and waking up a lithium battery n the event it is discharged to protection mode. Some Lithium chargers can wake up a lithium battery while its in power supply mode. I'll have to check to see if the Progressive Dynamics unit has this capability since it does use a power supply mode from what I've seen on my Victron BMV-712.
Also I'll include another video on depth of discharge that I've been conveying for a long time here where this ties into the lead acid charger discussion.

https://www.youtube.com/watch?v=sn5_CkQLJQI

The great lithium lie

https://www.youtube.com/watch?v=HCIlaXaVeF0

Jim

Jim,
The "Big Lie" video missed an opportunity to further explain some of the key differences between the batteries.

Yes, it's true a deep-cycle can be discharged below 50% but if allowed to stay that way for a length of time sulfation will "kill" the battery. In fact, the text from school states sulfation can start as early as 75% SoC. With what I know as of now, due to the chemistry difference, it doesn't hurt a LifePO4 to sit at 75% or even 50%. Don't you recommend storing LifePO4's at 50%? You'd never do this with a lead-acid.

A lead-acid is a "dumb" battery--it will keep discharging until it is completely exhausted of all energy. Can we all agree that taking a lead-acid to 0% shortens it's life? LifePO4's have a Battery Management System (BMS) which, at least in the case of the Battle Born, shuts off the battery before there is damage. (When a Battle Born turns off it's not "really" at 0%, or completely exhausted. When a BB turns off it's at a voltage level, that if allowed to drop further, will harm the battery so the BMS does not allow that to happen. At least that's how I understand how the BMS works...I could be wrong.)

I also found the "Big Lie's" statement to use manufacturer charts for comparison a little puzzling. I'm relatively familiar with the terms and concepts, but I couldn't begin to generate a life-cycle comparison between a Trojan deep-cycle 12v battery and a Battle Born (given the exact same usage profile). I wish the video's author had given an example. Morton on the Move's "Don't Waste Your Money..." video is the closest I've watched that does just that--but it's steeped in techno-speak. The bottom line from Mort's video is the LifePO4 have less life-cycle costs and provide more power over their life span. (And he's an electrical engineer...thus the reason for all the deep-dive into the numbers and theory.)

Howard

[Scott'n'Wendy]

Guest
howson
Thanks for the links. Good info.

[Guest]

Jim,
The "Big Lie" video missed an opportunity to further explain some of the key differences between the batteries.

Yes, it's true a deep-cycle can be discharged below 50% but if allowed to stay that way for a length of time sulfation will "kill" the battery. In fact, the text from school states sulfation can start as early as 75% SoC. With what I know as of now, due to the chemistry difference, it doesn't hurt a LifePO4 to sit at 75% or even 50%. Don't you recommend storing LifePO4's at 50%? You'd never do this with a lead-acid.

A lead-acid is a "dumb" battery--it will keep discharging until it is completely exhausted of all energy. Can we all agree that taking a lead-acid to 0% shortens it's life? LifePO4's have a Battery Management System (BMS) which, at least in the case of the Battle Born, shuts off the battery before there is damage. (When a Battle Born turns off it's not "really" at 0%, or completely exhausted. When a BB turns off it's at a voltage level, that if allowed to drop further, will harm the battery so the BMS does not allow that to happen. At least that's how I understand how the BMS works...I could be wrong.)

I also found the "Big Lie's" statement to use manufacturer charts for comparison a little puzzling. I'm relatively familiar with the terms and concepts, but I couldn't begin to generate a life-cycle comparison between a Trojan deep-cycle 12v battery and a Battle Born (given the exact same usage profile). I wish the video's author had given an example. Morton on the Move's "Don't Waste Your Money..." video is the closest I've watched that does just that--but it's steeped in techno-speak. The bottom line from Mort's video is the LifePO4 have less life-cycle costs and provide more power over their life span. (And he's an electrical engineer...thus the reason for all the deep-dive into the numbers and theory.)

Howard

Howard,

Lead acid batteries that remain at 100% SOC are most stable where anything below 50% SOC will degrade longevity. I believe AGM batteries may be capable of slightly lower discharges without affecting longevity.
Lithium batteries are most stable at their midpoint SOC of 50%. I asked this question directly to Battle Born and they agreed 50% SOC storage will maximize longevity. The BMS will protect the lithium battery but I believe the issue arises when its left in a discharged state and its normal rate of discharge takes it lower. I would like to know if the Progressive Dynamics unit will wake up a discharged lithium battery even though I never plan to run one down to below 20% SOC for lithium which is the 50% SOC for lead acid as a comparison. In reality, a lithium battery will also have longer longevity to stop a charge at 80% as well but honestly, this is unrealistic to do this unless the charger can be programed.

A little off topic here....is another video from Will on battery longevity. We practice this in a more sophisticated way with Hybrid batteries as an FYI.

https://www.youtube.com/watch?v=Yf9N9zBgyB8

Here is a gentleman who is setting his Victron controller to control to 80% SOC and to calibrate his float feature to use it as a hysteresis setting. Thereby keeping the float current off the lithium battery. The Geese offer a bit of humor. The key in this video is he can program out the float charge where with a WFCO, you cannot. This constant current applied to a lithium battery will shorten its life.

https://www.youtube.com/watch?v=6vTaCkTVl7I

Jim

[Scott'n'Wendy]

What chargers would the forum solar people recommend?
WFCO has the 9855LIS
PD had the 9160ALV
Victron......seems to put their chargers in a case with an inverter which I have no interest in.

[Yoda]

Yes, I understand. I have the Renogy 20/20 in my cart at the moment.
Curious about your varying alternator voltage, my system voltage (Dodge) seems to sit at 14.2 to 14.4 pretty much steady. Must admit I don't eyeball it all the time though. It's what made me think it wouldn't be 'horrible' at charging a LiFePO4?

Good morning Scott
First on the TV power connection through the 7 pin plug. On my unit the charge wire ties directly to the batterys through the GD power buss bar (constant hot side) The WFCO is totally separate wired into the distribution panel and then back to the buss bar through the GD feed through the disconnect switch, to get to the batterys, and would not change things while driving as it is off, unless connected to shore power. You may want to check how yours is wired. When I add the DC-DC I will disconnect it to prevent back feed.

Now as to charge voltage - on my now gone 04 F350 6.0 I was seeing 14.4 to 14.8V at the plug depending on engine speed.. However its really the charge Amps that do the work. I never check that on my system but in other posts folks were seeing 4 to 8 amps. At that level it will take a while to even begin to charge any battery.

In my discussion with Crown when I had the inverter battery issue (major initial voltage drop under load) ,is was the charge amperage (along with correct voltage) duration that made a huge difference in how the batterys behaved during discharge. I had to change the profiles and charge current duration's. I thought I had the correct up in my Multiplus but needed to change the equalization time and voltage (3 to 4 hours every 30 days) to improve performance. While I did not understand the logic, it worked. That's why I chose the 60A DC-DC unit as the batterys like the higher amp charging.

Just food for thought as normally I let the smoke out of the wires

Learning a lot here folks - thanks for the great information and links

Keith

[Yoda]

What chargers would the forum solar people recommend?
WFCO has the 9855LIS
PD had the 9160ALV
Victron......seems to put their chargers in a case with an inverter which I have no interest in.

Scott
Victron does have a few stand alone chargers
https://www.victronenergy.com/charge...ip65#downloads
https://www.victronenergy.com/charge...harger-12v-24v
https://www.victronenergy.com/charge...-24v#downloads
But I know nothing about them. If you replacing your existing converter be sure the output at least matches your current one. I believe you need something where you can adjust the profile to you needs. Before I settled on the Multiplus I was considering a Progressive dynamics unit and another recommended by Battle Born on thier web site.

I am sure the experts will be along shortly.

Keith

[Guest]

What chargers would the forum solar people recommend?
WFCO has the 9855LIS
PD had the 9160ALV
Victron......seems to put their chargers in a case with an inverter which I have no interest in.

Scott,

I mounted a PD 9160ALV in the passthrough. Not familiar in how well the WFCO functions but the PD unit works perfectly. Also on the board is the 20amp Renogy DCDC.

Also installed a Victron MPPT 75/15 controller on my suit case 100W solar panel.



Jim

[Scott'n'Wendy]

Guest
And, if I understand correctly, the outputs of the Renogy 20/20, the PD9160ALV, and the Victron MPPT can all be connected together (to the batteries) with no issue?

And why did you choose the victron mppt over the renogy of similar specs?

[Guest]

Guest
And, if I understand correctly, the outputs of the Renogy 20/20, the PD9160ALV, and the Victron MPPT can all be connected together (to the batteries) with no issue?

And why did you choose the victron mppt over the renogy of similar specs?

Scott,

The outputs on the Renogy and the Progressive Dynamics units are connected to a common bus bar. I have not used the solar panel but it connects through the solar plug on the side of the rig which is routed to the battery. The solar would only come into play if I ran my generator while powering the Progressive Dynamics unit. I will refer you to Howard in how these may play together since I've not tried it. Either overall voltage and load would be controlled or they would fight one another. Not sure.

Jim

[howson]

Scott'n'Wendy

With the exception of the Renogy and the Battle Born batteries all my equipment is Victron--which is made to work together. When I engage the Renogy (when towing) I can see the 40A flowing to the Battle Borns (using the VictronConnect app) so I know it works.

[Guest]

Scott'n'Wendy

With the exception of the Renogy and the Battle Born batteries all my equipment is Victron--which is made to work together. When I engage the Renogy (when towing) I can see the 40A flowing to the Battle Borns (using the VictronConnect app) so I know it works.

In the auto industry we would use a third controller to set arbitration. I could see setting solar as the priority as long as it is delivering. This would aid in fuel economy.

Howard can you see the solar and Renogy contributions separately?

Jim

[howson]

In the auto industry we would use a third controller to set arbitration. I could see setting solar as the priority as long as it is delivering. This would aid in fuel economy.

Howard can you see the solar and Renogy contributions separately?

Jim

Yes. The solar or the BMV-712 via the VictronConnect app (I can choose the BMV-712 or solar controller separately). The BMV will give the total going to (or coming from) the battery and the solar controller what the panels are contributing / generating.

[Guest]

Scott'n'Wendy Scott looking back I did not answer your question on the Victron. The reason I chose the Victron MPPT with Bluetooth was to have common monitoring via the Victron app with the BMV-712. I also like the programming of the Victron MPPT where I tailored the charging to my AIMs LiFeP04 battery. Battle Born also has charging recommendations for the Victron unit and will even sell this unit pre-loaded with their charging parameters. My suitcase solar panel came with a cheap PWM controller and was not programmable for Lithium where the Victron MPPT gave me the flexibility I was after.

Since no other chargers would be ran with the DCDC at the same time. there is no concern. Next spring, I will bring the solar panel with us to our PA campsite to test this along with the Progressive Dynamics unit to see how they play together. From Howards input, I would expect them to control but if there is an issue I would simply unplug the solar panel when running the generator and the PD converter charger while boondocking.

Jim