Lithium Battries again!!

Joined
Mar 21, 2010
Posts
2,545
Likes collected
3,079
Funster No
10,727
Further to my recent posts regarding Lithium Batteries. Some say you can’t swop like for light lithium/gel

I have had two replies from two different suppliers of Lithium Batteries and read as:-

SUPPLIER A
“Hi thank you for your enquiry. Your charger will work with ********** batteries either a GEL setting or AGM setting is fine. The benefit of *********. batteries they are a drop fit to lead acid batteries and the BMS ensures the chargers do not harm the battery”

SUPPLIER B
“I don’t think you’ll need any addition modifications to your motorhome, it is possible you’ll need to change your battery cable terminals from pole to stud terminals “

Still very confused

Colyboy
 
Speak to mick at SAP Doncaster .
They fit lithium to ambulances and see what he says.
 
Have picked up from this site that charging a lithium directly from the engine’s alternator needs to be investigated , as might be an issue.
 
Looking at Super B web site they do one LiFePO4 that they say is a direct drop in replacement but they do say that it requires a Battery to Battery type charger to charge from a Euro 6 vehicle alternator.


Martin
 
Further to my recent posts regarding Lithium Batteries. Some say you can’t swop like for light lithium/gel

I have had two replies from two different suppliers of Lithium Batteries and read as:-

SUPPLIER A
“Hi thank you for your enquiry. Your charger will work with ********** batteries either a GEL setting or AGM setting is fine. The benefit of *********. batteries they are a drop fit to lead acid batteries and the BMS ensures the chargers do not harm the battery”

SUPPLIER B
“I don’t think you’ll need any addition modifications to your motorhome, it is possible you’ll need to change your battery cable terminals from pole to stud terminals “

Still very confused

Colyboy
Well you can keep asking the same question and you will keep getting conflicting answers.

Buy the batteries from someone claiming you don't have to make changes, get it in writing and when they blow up, catch fire and burn everything in the vicinity you can write and make a complaint;)

You will need a Battery to Battery charger, and you will need a charger that has the correct charging profile for Lithium batteries. "IF" you have a motorhome that has a charger with a Lithium charging profile "AND" you have a motorhome that has a Battery 2 Battery charger then, under those circumstances you could drop a Lithium battery in a direct replacement!

Subscribers  do not see these advertisements

 
Check what the supplier claims with what the manufacturer says. Relion say you can use a GEL setting on a mains charger but warn that some alternators can be damaged, which is why I have a B2B.
 
There was a U-Tube video which dealt with the charging regimes of both Alternators and EHU systems with various batteries. but try as I may I cannot find it!.
 
Hello Colyboy

Most vendors will advise within minimum manufacturer guidelines, enough to pass the warranty period. On both of your examples, theoretically they are right. They rely on the internal bms, failsafe protections and relay disconnect. Some don't tell you, if used with solar panels and disconnects the charger, you may damage the charger as is still connected to solar but no battery.
One manufacturer, actually states this very clear on their SuperPack battery models so the installer has to make provisions if battery disconnects when outside parameters. Most of these monolith 12,8v batteries, come with bms inside and relay disconnect. That's why you can't really kill them if they drop in to replace of Lead. But it accelerates their aging 4 times faster.
To get the best out of them, ALL charging sources needs to be compatible with lifepo4 charging parameters, or at least a custom input settings. You need a B2B from alternator for sure, to limit charge, or at least a dc-dc converter, with adjustable output voltage and a switch to stop charging when the engine is off, or when no charging is required.
I got LiFePo4 in my van and I can't envisage a 5kwh reserve capacity with Lead, unless you got a 300kg spare pay load. The charge and discharge rate is fantastic and I run some very conservative settings to protect battery health, a lot lower than what manufacturer recommends. They want me to buy again in 2 years, I want to preserve battery life.
There is good history among the off grid users, with 8 years plus of usage and no degradation. These ppl run on custom settings that are well below the manufacturer recomendations.
 
Much ado about not very much!
If the Lithium has a built in BMS, (battery Management System). then it is drop in.
Nearly
The lithium can take a bigger charge than the lead and charges far faster if the alternator can deliver.
The hitch:
If your vehicle has an intelligent alternator then you might need a B to B, battery to battery system.

some luddites are scare mongering about fires with lithium batteries. There have been pictures of the Tesla, a car which carries over a ton of batteries can accelerates 0 to 60 in 2 seconds and some versions can travel at 250mph. the motorhome battery is less than 15kilos.
Jan to April 2018 - up to 3 days without hookup, before my EBL complained that the voltage was low.
Jan to March 2020 up to 3 months and my EBL has yet to complain.

Subscribers  do not see these advertisements

 
There have been pictures of the Tesla, a car which carries over a ton of batteries can accelerates 0 to 60 in 2 seconds and some versions can travel at 250mph. the motorhome battery is less than 15kilos.
More importantly a Tesla battery is an entirely different battery chemistry of Li-NiCoAlO2. Not the LiFePO4 chemistry we are talking about. The only thing they have in common is lithium and that is not a problem.
 
Informative video.
For those of us with older controllers 1999.
IF I wanted to use a lithium battery I know I can switch my solar controller to Lithium setting.
BUT I assume I would also need an additional lithium compatible battery charger for when on hook up?
So I could sacrifice a 3pin socket in a cupboard I have and plug in a suitable separate charger. But how do you stop the onboard controller trying to pump power TO the lithium?
 
I assume you mean the battery charger when you say "on board controller" I suppose the first question is what on board controller do you have?
 
I give up you, never listen to any advice.
How many more times do you have to be told, if you want you Lithium batteries to last you need to use a proper charger for them.

Subscribers  do not see these advertisements

 
I give up you, never listen to any advice.
How many more times do you have to be told, if you want you Lithium batteries to last you need to use a proper charger for them.
Lenny HB I don't recall that I have asked before and thought this might be useful information for other people to read?
 
I assume you mean the battery charger when you say "on board controller" I suppose the first question is what on board controller do you have?
My Onboard controller is from 1999 and is a BONUS PLUG-IN SYSTEMS PMS5BWAH. Hence i do NOT believe it will be capable of correctly charging Lithium. In fact there are no adjustments for the onboard controller i am aware of. Duifficult to see through the perspex window but right hand breaker says "Charger and Lights". So perhaps if I turn that circuit OFF, then the charger circuit (and lights) will be dead. Leaving an onboard charger to do it's job.

1585413149048.png
 
Last edited:
I have gone through the process of installing lithium batteries.

The new generation which claim plug and pray have a BMS system built in. this board allows the lithium to pretend that it a lead battery. It can therefore work with lead charging systems.

The older generation does not have a BMS and this must be supplied separately.

These lithiums trip up when installed in a vehicle (modern Mercedes) with an intelligent alternator, and the start battery is lead.
1585427565926.png

Subscribers  do not see these advertisements

 
Have picked up from this site that charging a lithium directly from the engine’s alternator needs to be investigated , as might be an issue.
Yes, I read the alternators might burn out at low revs as the current acceptance of Lithium is much higher with little resistance. The alternators are fan-cooled and when they do not have resistance the current supplied is greater than the ability of the fan to cool it at low (tick over) rpm, it then burns out the coils, UNLESS, the alternator is a smart one with an internal temperature probe to control the charging rate, the battery BMS is to protect the BATTERY, not the charge source.
I think my MB has one but cannot confirm. Ordinary vans do not have them.
 
I have gone through the process of installing lithium batteries.

The new generation which claim plug and pray have a BMS system built in. this board allows the lithium to pretend that it a lead battery. It can therefore work with lead charging systems.

The older generation does not have a BMS and this must be supplied separately.

These lithiums trip up when installed in a vehicle (modern Mercedes) with an intelligent alternator, and the start battery is lead. View attachment 372688
Can I ask which LiFePO4 you have?

I ask because I have lithium (2 years) and did a lot of research back then on what's needed. Then, there was no such thing as a drop in replacement. They are so different. Maybe it's changed now?

Mine has a BMS (very good one) but still needs regulated voltage, something to stop it killing the alternator, low temp protection and a lot more. I have all this so not an issue. Curious if a stand alone solution now exists though?
 
Sorry.
Slipped to bottom of thread cause sure I have read it all before
Can you just drop lithium in a
van... in my view maybe.. but i have. but only if you rely on solar (with appropriare lithium control setting charge controller) and when on EHU (which is very rarely) and you use s dedicated freestanding lithium charger then yes . The problems start IMO when you start charging from alternator then yes you need to make changes.
 
I think my MB has one but cannot confirm. Ordinary vans do not have them.
My MB was of the same type and age and did have a smart alternator. I fitted a B2B because the alternator charging of the leisure battery was very limited. As soon as the engine requirements were met the charging voltage dropped off saving fuel but leaving the leisure battery under charged.
 
Can I ask which LiFePO4 you have?

I ask because I have lithium (2 years) and did a lot of research back then on what's needed. Then, there was no such thing as a drop in replacement. They are so different. Maybe it's changed now?

Mine has a BMS (very good one) but still needs regulated voltage, something to stop it killing the alternator, low temp protection and a lot more. I have all this so not an issue. Curious if a stand alone solution now exists though?
I purchased my battery from Transporter energy. end 2018.
It was in principle plug and pray.. The issue was with my motorhome a 2016 Hymer MLT560 on a sprinter chassis. In the manual written clearly, the EBL 30 treats the 2 batteries as one. when they are both the same from the factory (lead) the alternator pumps electricity until the potential difference (PD) is up to 12.5 volts.
When a lithium battery is introduced, it reports a PD of 13.25volts or thereabouts to the EBL. The alternator then says, I can go to sleep to save fuel. The lithium battery then has to take on the task of running the electrics of the van, till it's PD goes down to 12.5v. the alternator then starts to work.
To confuse the issue, when the sun shines, the lithium is charged from the solar panel.
This alternator issue was fixed by installing a Schaudt WA12125 BtoB. This device tells the alternator to keep working till both batteries are charged.

as mentioned somewhere else, when I had AGM batteries the EBL 30 would peep once to warn of low battery, when it peeped 25 times it would then switch off the habitation electrics to prevent damage to the habitation battery.I could go 3 days without sunshine, I just gone 3 months.

There is a lot more science (electrics)behind the system than I can explain. for example Hymer in Germany offers a lithium add on where you do not have to ditch your AGM battery. I haven't found anyone in England who knows how they do it.

Subscribers  do not see these advertisements

 
They do it with a B2B isolated charger. I’ve done it as well, to avoid paralleling two different chemistries, that work on different parameters.
 
There's no reason in theory why you can't have a battery with a BMS, B2B and anything else integrated into it. The problem is, a battery has a finite life, and the expensive electronics would be ditched when you recycle the battery. Now that LiFePO4 batteries can last over 10 years with proper care of their charging and discharging levels, it is becoming feasible to integrate charging control systems stuff into a battery.

If this becomes more prevalent we will need very much more information about a battery than just its capacity and the fact that it has a BMS, if we are to trust that it is a 'drop-in replacement'.
 
The BMS does cell balancing and protects the battery from over and under voltage and temperature by shutting it down. It does not adjust the charging voltage or amps, this is the job of the separate charger, B2B or regulator.
 
They do it with a B2B isolated charger. I’ve done it as well, to avoid paralleling two different chemistries, that work on different parameters.
Would it be possible to transfer the knowledge in a simple manner. I have a beautiful nearly new AGM battery in my garage that I keep charged in case I find a use.
 
Would it be possible to transfer the knowledge in a simple manner. I have a beautiful nearly new AGM battery in my garage that I keep charged in case I find a use.

Yes no problem. When you charge two batteries from the same source, ie: alternator, they end up in parallel while charging. To avoid that you can use a DC-DC converter, isolated, between the source to the battery being charged. Isolated means the -negative is not shared. Since a LFP at float is 13,4v and Lead at 12,6-12,8v it is obvious if these two are paralleled, will be a huge transfer of energy from one to the other. Same goes on the absorb scenario, where Lead will absorb at 14,4-14,8v, way to high for LFP and the bms HVD will be triggered
Many will say is ok but not for long term. It will probably see you out the warranty but that’s not acceptable. That’s a consumerism approach, pushed by the sales man. So, if you want to charge two separate working voltage batteries from a common source, you use a isolated dc-dc converter. It will keep the batteries completely isolated at all times, and charge at different parameters in the same time. The dc-dc converter used, has to be configurable so you can dial in your voltage requirements. Victron does a beautiful battery to battery 30a Orion smart, or use one at almost half the price, from the same family: Orion isolated. Other manufactures do B2B chargers but I don’t know if they are truly isolated.
Hope this helps.

Subscribers  do not see these advertisements

 

Join us or log in to post a reply.

To join in you must be a member of MotorhomeFun

Join MotorhomeFun

Join us, it quick and easy!

Log in

Already a member? Log in here.

Latest journal entries

Back
Top