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Lithium Battery

Where can i find the Low Battery voltage setting?

I've got a system with 400ah of 48v LiFePo4 batteries and I'm constantly getting low battery Voltage warnings. But they seem to be set at 52.08 volts which seems a bit high.

I have an ESS running in Battery life mode. Images of setting below:

I can't for the life of me find the setting that is causing this alarm. Can anyone point me in the right direction?

Can I also get a sanity check on my settings? Including recommended settings for the DC Input Low Voltage Shutdown?






de1nonly asked
de1nonly answered ·

2 Answers

Can I run two lifepo 100ah batteries in paralle, which have 2 different max charge currents?

Problem is, the only spec I am finding hard to match on new battery I wish to purchase (to run in parrelle with the one that I already own,) is max charge current. One is 100a and other is 50a. Is there any way that this can work?

heyho asked
heyho answered ·

2 Answers

A different LFP imbalance problem

I have charged two brand new Victron LiFePO4 25,6V/200Ah Smart batteries separately in order to connect them in series for a 48 V system. Charging setup includes Blue Smart IP22 24/8 charger, SmallBMS and Cyrix-Li-Charge 24/48-120. One of the batteries was charged and balanced OK.

The other battery was charged OK in terms of voltage but it still indicates imbalance in VictronConnect. Also last full charge is "Unknown" even if the charger had after bulk and absorption reached storage status. Maximum voltage difference between cells is only 0,01 V. Obviously this battery is in fact well balanced but it doesn't appear in VictronConnect. How could I wake up its "balanced" status?


Simo Hassi asked
klim8skeptic commented ·

3 Answers

SmartSolar MPPT 100/30 and LiFePo 24V 200Ah


Is the SmartSolar MPPT 100/30 able to deal with a LiFePo 24V/200Ah battery pack ?
Battery Pack has integrated BMS 8S 200A (also RS485/CAN)
Plan to connect 2 x 395Wp (44.7V) PV panels in series connection.

appreciate feedback

best regards,

alphalinux asked
Alexandra commented ·

1 Answer

V-TAC LFP batteries, trying to source information

There's a new distributor of LFP batteries in Europe for a couple of months now, under the V-TAC brand. V-TAC was founded some 20 years ago at UAE and has a very strong presence in Europe, particularly eastern Europe and the UK. They've been hard into the LED and lighting business. They've recently started offering LFP batteries for solar projects, along with other energy bundles of dubious quality. I am interested in their 10kWh model (model name: AT48-200H or VT-12040), since I can source them locally for under €250/kWh and they come with a full 5-year warranty.



It's an certainty that their 10kWh model is a branded generic Chinese unit, however you can't argue that at this price, it's a no - brainer, particularly for smaller installations.

I am trying to figure out the model of their BMS and whether there is any chance of it getting along with an ESS GX setup, either officially or through Louis' excellent serial tool. Here's a photo of the BMS they are using, in case it rings any bells (searching for "CPES-BMS16S" online wouldn't produce any results):


They have published lots of documentation on their website for all models, and there's also a compatibility chart that displays Victron among the compatible brands; it doesn't mention to what extent, though.

I would appreciate any additional information or insights.

Here's the manual, including communication ports pinout

VT-12040 - manual.pdf

thanar asked
thanar edited ·

0 Answers

12 volt lithium Smart battery SOC on delivery?

I have recently taken delivery of 12 x 12V Victron Smart lithium batteries. I expected them to be around 50% SOC but in fact they were either 100% SOC or within 2% go that. Is there something wrong here or have I been misinformed?

jonathanmosse asked
Alexandra commented ·

0 Answers

Orion DC-DC, AGM, Lithium & Wakespeed

Hi all,

I am trying to understand the best way to charge both Lithium (House) and Led Acid (Start) incorporating a WakeSpeed regulator.

There are various diagrams online but it’s not totally clear how the combined setup works.

Would one of the two set ups below work? Or does anyone have a simple diagram to visualise the correct approach? Thanks.


colm asked
colm edited ·

2 Answers

Cegasa SolarGreen configuration with Cerbo GX

Has anyone successfully configured a Cegasa Solargreen battery system to a GX device.

I cannot get the Cegasa to appear on the device list of the Cerbo?

The system consists of 2 X Cegasa Solar Green 5160, 1 X TCC CAN, 1 X Cegasa Hub Com, 1 X Multiplus II 48/3000, 1 X Cerbo GX, 1 X GX touch. ESS system.

The Firmware version on the Cerbo is 2.93. The TCC CAN is not a v02 - does it need to be?

I have tried a number of TCC CAN unit and hubs?

Please get in touch if you can help.

anthony asked

0 Answers

Solar Controller & Battery Charging


I am a newbie, so terminology might be off. I have a 100/15 solar controller, 100 watt solar panel, and 2 -100ah lithium batteries in parallel. Also have a victron shunt. The amps shown on battery shunt seem quite low compared to the amps flowing from the solar. Can't figure why those numbers aren't the same or close. What do I need to check?

kmm asked
Kevin Windrem answered ·

1 Answer

Best 48v BMS

Hi everyone,

I am expecting a shipment of 16x280Ah prismatic LiFePO4 cells. It is my first experience with non-lead acid batteries. I understand that I need a BMS, but there is incredible selection and profound difference in cost between models. I currently have a Cerbo GX which I understand has two data busses, a CAN bus and a proprietary VE.bus. This paragraph is the entire sum of my BMS knowledge, +/-.

I want to find a BMS that integrates maximally with the Cerbo. I'm happy to pay for quality. I don't necessarily need it to be a "supported" solution by Victron, as long as it integrates well. In another group on DIY Powerwalls, Batrium seems to be the most popular name in BMS. Is anyone running a similar system to what I've described, with a Batrium BMS?

What other options do I have? I'm also impressed with REC-BMS, but it's very pricey. A couple other ones I've glanced at are 123Smart BMS, Tiny BMS, Chargery BMS and DIY BMS. Also Daly?

The two most important things to me are 1) safety and 2) integration with my Victron products. This will be a 16s, 48v (although it's not a strict design requirement) LiFePO4 battery with low-moderate current requirements (probably something like a 3000 watt inverter). Thanks for any input!

whafa asked
djdemond answered ·

10 Answers

Alternator replacement with lead acid starter and Lithium house

I am planning to replace my Volvo standard alternator (which has a built in regulator) with a Balmar model and an external regulator. My current set up is shown in the first diagram. This works, but has the disadvantage that the lithium charging is limited to the output of the DC-DC converter.


Is there any reason why I cannot re-arrange the components to use the DC-DC converter to charge the starter battery instead (see second diagram)? My reasoning is the output of the DC-DC converter is more than adequate to replace the entry used for starting.


billaylward asked
billaylward commented ·

2 Answers

voltage spike during absorption on multiplus 3000 12v with LiFePo internal BMS

Hey folks, I have a similar set up to the post here.

The main difference: I have is a single large 360amp/h battery from expion also internal BMS.

Using the latest Multiplus firmware applied via the android app.

I'm seeing similar behavior where the multiplus will bulk (90amp limit) to 14.2 (my setting) and start absorption. tested with discharge to 95% so I'm not watching the output all day.

The voltage will then creep up to 14.3-14.4 (multiplus perspective) which is above my set desired set voltage (confirmed with multimeter). Near the highest sustained voltage I see a similar amp spike as the related post followed by a voltage spike (~16.1v) for less than a second. (See attached video of the system return to pre spike voltage). Note the V drop from the multi plus to the battery is 0.08-0.09v.

The manufacturer has confirmed the BMS will cell balance at top of the charge and has recommended 14.2 - 14.4 for 1 hour in absorption and doesn't believe I should be seeing this behavior.

  • They suggested removed all temperature cables. Temperature is provided by the lynx shunt, and lithium profile is selected for no temperature comp on the multiplus. Can this be the issue anyway? I would rather not remove the temperature sensors.
  • Would lowering the voltage further have a benefit e.g. 14.1 vs 14.2? as it seems the multiplus allows voltage to exceed the settings.
  • Out there idea: any issues fitting an Alternator protection device in series to prevent these voltage spikes if the BMS is exhibiting normal behavior?

Next steps I'm considering

  • Call the battery manufacter again and confirm cell balance behavior
  • Repeat testing without multiplus and let mppt do the charging to see if the issue is isolated to the multiplus. Note: during the above discription the solar panels were off.
  • Lower voltage to 14.1 if acceptable
  • Other...??? Any other ideas from the community to test?

mattguy asked
mattguy commented ·

4 Answers

DC-DC Orion setup for charger mode

Hi all,

I'm planning to set up a DC-DC Orion converter to charge a Victron LiFePO4 house battery in charger mode (coupled to a starter battery, the latter powered by an alternator). Does the chemistry of the two batteries have to be the same? In other words, do I have to replace the engine starter battery with a LiFePO4 starter battery (for example, a pair of DL+ 12V Dakotas for a 24V system)?

romeobravo asked
Stefanie (Victron Energy Staff) commented ·

2 Answers

Choice of charger 12V

Looking for a charger with two output for charging two separate batteries, one LiFePO4 and one lead-acid battery at the same time.

Have looked at the Blue Smart IP22 Charger with three outputs. As I understand it, this charger has the same settings for all three outputs?

Any suggestions for a charger that can charge two battery banks (lead-acid and lithium) at the same time?

EasySolar charges lithium, but needs a little extra charging at times. Will also install a system (lead-acid and lithium) in another boat that does not have EasySolar.

Boating and have equipment below:

  • EasySolar 12V, 1600V
  • SmartShunt 500 A
  • Cerbo GX
  • Digital Multi Control 200/200A GX

falnes asked
oldwave answered ·

3 Answers

Add a second LiFePO4 battery bank - is my schematic ok?

Dear all,

For those interested: I'm going to add a second battery bank to my parents' installation.

This is the existing schematic:


I would modify the system using:

15 (not 16 as mentioned initially) times a 3.2V 200AH prismatic LiFePO4 cell, so 15s configuration. (click to open)

A would use a 16s 300A Daly BMS (because I hear nothing but good things about this BMS) (click to open)

Basically I would connect the now 15s (not 16s as mentioned initially) battery in parallel with the other 15s6p pylontech batteries.

Given that each battery in the future system will be connected in parallel, and each with it's own BMS, I don't see a problem;

The schematic would become (adding my homemade battery):



In practice I would simply add the homemade battery to the 2 copper bars, since there is room (free holes):


In theory I could add the system to VRM using CAN cable between Daly BMS & Victron Venus GX, but I don't think that's really needed. But it would be nice to see the battery in the system overview so that my dad can monitor it.

Please let me know if I'm being realistic or about to make a huge mistake.

hdb asked
derrick thomas answered ·

4 Answers

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