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Mixing la and lithium - is there a definitive answer yet?

Hello all. I know this has been discussed quite a bit in different threads, but I was just wondering if anyone has come to a conclusion yet. I know I have to spend a ton of money on new lithiums (looking at US3000s) but I don't want to have to bin the la set. If it's still generally considered a bad idea to mix, then has anyone come up with a design for a parallel setup with some sort of manual switching?

Paul Carmichael asked
Paul Carmichael commented ·

1 Answer

Cerbo GX white screen, equalize problem.


When I connect to the remote console, I only get white screen. All I did was reboot and then this problem appeared.
I can't adjust any settings anymore. Cerbo has been updated to the latest version 2 months ago (v2.94) Automatic updates are not turned on.

Naturally, I can no longer access the reboot menu. I tried turning off the power manually, but the problem persists.

Edit. It suddenly started working again.



I almost always have to restart if I want to equalize the batteries. Is this related to this same problem?

Often it just says "starting". After a reboot, equalize works. The problem has been there for 2 years.

kane-1 asked
kevgermany answered ·

2 Answers

Boat: flooded starter and AGM house battery charging with Phoenix Smart IP43 (3-outputs)


Can someone please advise.

I am building a boat system:

1x AGM battery (Victron 130ah) for house/system.

1x Flooded battery (VARTA LFS95) for starter (>850 CCA required, AGM not recommended by outboard manufacturer).

I have a Phoenix Smart IP43 charger with three outputs and a separate Battery Smart Sense module.

Will it be OK to charge both (house and start) batteries at the same time using separate charger outputs?

The smart sense would be connected to the AGM battery.

Or would it be better to install a battery selector and connect the house battery lead to to the charger output only when it is needed (with AGM disconnected during that time)?

Erikas Berzinš asked
Mike Dorsett answered ·

1 Answer

An Alarm for SOC Mismatch with Battery Voltage?

The following is a question if such an alarm is desirable, feasible, and practical:

As state of charge readouts have become more and more common, the rate of people reporting problems with accuracy is increasing and I regularly come across the situation where a customer believes their battery bank of some years is fine due to reported state of charge being only 80 to 90% minimum but after assessing their battery voltage dynamic it's clear they are taking the battery into real 0% SOC territory, often daily, and unknowingly damaging the battery. Typically the battery monitor has been setup properly but something else has changed, most commonly due to aging and use the battery has lost capacity so the SOC values show as higher than they really are.

Originally I had thought surely there's a way that battery monitors could recalibrate and set themselves to the real capacity but this gets complicated... what I do think could be a real improvement and put forward for consideration is an alarm when the SOC and battery voltage seem too mismatched. Obviously the values would need to be considered and refined but the logic could work something like this:

If SOC >60% and Vbat < 0.96Vnom for 10mins with current of <3% of Bcap then report "SOC Mismatch - Please synchronise battery monitor or test battery capacity"

I think these conditions are clearly incorrect enough to avoid nuisance alarm, apply to most battery chemistries, and could prompt people to check out their system before further damage is done.

In the immediate era, this applies most to older lead acid installations, but as the large number of new lithium installs gradually lose capacity, the potential mismatch presents a significant threat where decisions based on calculated SOC may not come in at the right time, risking hitting very low real SOC or BMS cutout.

owen-spa asked

0 Answers

Exploded flooded acid batteries

In one of the cottages at our allotment park, a lead-acid battery has exploded. Fortunately, there were no injuries, only material damage.
I examined the installation but initially couldn't find a cause. The installation consisted of two solar panels, a Victron charger, and two flooded acid batteries. Below are the specifications of all components:
Solar panels - 2 pieces connected in series:
Pmax 370 W
Maximum Power Voltage 35.2 V
Short Circuit Current 11.5 A
Maximum Power Current 10.52
Batteries - 2 pieces:
Flooded acid 12V 240 Ah
Victron MPPT 100/30 switch position 0

I connected the charger to another installation and measured a voltage of 15.2 V during bulk charging. At this voltage explosive oxyhydrogen is formed.
Is my conclusion correct that the Victron MPPT 100/30 only is suitable for charging flooded acid batteries if the maximum bulk charging voltage is set lower?

hennyv asked
klim8skeptic answered ·

2 Answers

Basic lead acid battery settings


I have a MPPT 100/50 with basic 12v flooded sealed lead acid battery’s 4 x 110a.

I can’t see in the manual any settings for the rotary switch for basic lead acid.

What should it be?

Or do I need to put in expert mode and change the charge settings?

What’s the best settings for simple lead acid.


Simon Coram asked
gazza commented ·

1 Answer

OrionTR and SmartShunt parameters for a Renogy Deep Cycle AGM Battery 12 Volt 100Ah

Variations of this question popped up before on this forum, but here I go with my specific need. I need the config settings for an Orion TR (non-isolated, if that makes any difference) charger for a Renogy Deep Cycle 12V 100Ah AGM battery (they call it a "valve regulated sealed lead acid battery").

The Renogy website has an FAQ which only mentions the following:

"7. When using a charge controller, which battery type should I set? You should choose the SLD battery settings."

What does SLD stand for and how to apply this to set up the Orion charger?

Also I am monitoring this battery with a Victron Smart Shunt 500. Any special config for that ?

Thank you all.

koenbro asked
koenbro edited ·

2 Answers

Low battery alert

Hello everybody! Here another puzzle for lead batts addicts!

In my offgrid mountain house, managed by Victron, my 30kWh/24V OPZS batts are at -4°C (outside -12°C). This morning the voltage suddenly fell from 22.4 to 20.2Volts triggering an alert. Apparenlly everything is working well: inverter, CCGX and VRM, Modemrouter with a constant load of 112W (5A) . For the last 20 days, I never reached SOC=100% but il never went under 80%

My explanation is a bad measure of the voltage, due to a bad contact, due to the low temperature. So "Wait and see".

Anyway, with so old (?) batts I am prepared to buy a new set, but that would be when the snow has thawed (May?)

Anyone with a better understanding?

Lionel SEYDOUX asked
Lionel SEYDOUX commented ·

1 Answer

Lead acid battery

Hi all. i have the orion- tr smart isolated dc/ dc charger. I’m after the settings to charge leausure lead acid batterys. Any ideas anyone.

stevendax asked
kevgermany answered ·

1 Answer

Techniques to extend battery life of Lead Acid Batteries

My batteries are almost 5 years old now. Unfortunately in the past year we had severe grid electricity outage so my batteries have been exhausted by multiple deep cycles of discharge. My system uses a 24 Sunlight 2v - RES 8 SOPzS 1380 batteries. What I am facing now is that voltage drops dramatically as batteries reach 60-65% (drops below 44v). I am wondering if there is something I can do to try to extend their battery life to try for at least 1 year or 2 years. Thanks!

samer-abi-chaker asked
scraggs answered ·

1 Answer

Victron 160AH Lead carbon batteries

Hi I've seemed to have lost a lot of capacity in my battery bank 8x 160 AH Victron lead carbon, they were new in mid 2019 so just over 3 years old, the BMV has recorded 104 charge cycles and 507 full charges ( sync to 100,%) our average discharge is 107ah, we now get a low voltage warning around 80ah, basically we have to run the generator in the evening to get something like 90% change if the solar hasn't got it above 90% or we end up with low battery warning in the morning or shutdown with voltage about 38 volts, the battery settings are hopefully in the picture below with the history page.

I've spoken to my dealer he's essentially said out of warranty and buy new lithium! I'm off grid so totally dependent on the battery bank, I've checked and cleaned all the terminals my next option is possibly removing 4 of the pack and getting them tested and charged with mains power to see if they are still usable, interested to know if this is normal for 3 year old batteries or if something is setup incorrectly?


Martin asked
kevgermany commented ·

3 Answers

Lead Acid Battery with MPPT 75/15

Hello all,

I have on MPPT 75/15 a SMF C100 lead-acid battery with the following data:

Charge current Approx. 1/10 of the C20 nominal capacity (C20: 80Ah but I have 100Ah).
Charging voltage 14,7V - 14,8V
Float voltage Max. 13,8V

The parameters for charge voltage and float voltage are clear. I am unclear what settings I should enter for equalization voltage, maximum charge current and cell equalization. Does anyone have a tip for me?

Thanks already!

ben-real asked
bill-walter commented ·

2 Answers

Lithium/Lead Acid battery bank

Hi, I have a narrowboat with 4 x 110ah lead acid batteries monitored by a BMV 702 and connected to a MPPT 100/50 Victron controller and a Multiplus 12/3000/120 Charger/Inverter.

I am looking to optimise the performance and life of the batteries and came across the combination of Lead Acid and Lithium Batteries in parallel which appear to complement their charactistics for optimum performance and Lead Acid battery life.

It appears that the recharge for the batteries is where this system falls down. Am I correct?

If this is the case, has anyone tried to separate the batteries during charging then reconnect for discharge? Would this overcome the problems in charging?

Your advice gratefully recieved


mr-frankie asked
pwfarnell answered ·

2 Answers

Charging profile for EFB lead acid?

I just bought an MPPT 100/15 as an upgrade to my system but disappointed to find there's no profile for lead acid batteries. Expected more from such a high quality controller.

I'm using a varta LFD90 EFB battery but the manufacturer does not supply any data for a charging profile.

Can I use one of the default gel profiles or will it damage the battery by staying too long in the absorbtion stage?

It's for a micro camper for occasional weekend use that will have an 80w panel on the roof which I want to use to ensure the leisure battery gets a more complete charge than the split charging system can give it.

Been all through the website and this forum and found very little information that wasn't vague or unhelpful.

I can't believe victron would sell this product without even considering that someone might want to use it with lead acid leisure batteries!

twistedvegan asked
helzy commented ·

0 Answers

Which battery technology is most suitable for use in microgrid systems ?

Hello, I hope everyone is well. From a literature search, I found that people are using lead acid batteries as an energy storage source. but from other battery researchers, they suggest using li-ion batteries for microgrid applications. so my question is what type of batteries are most used in microgrid applications?

ayoub-rahmouni asked
Alexandra answered ·

1 Answer

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