Anyone replaced the under-seat battery with this 150AH KS-Energy Lithium?

[a892374923874]

This battery on its side almost exactly matches the dimensions of the rubber cover over the Varta LA80 under my 2019 Beach passenger seat.

KS-C155B 12v 155AH Compact Series Bluetooth High Power lithium leisure battery - KS Energy UK

KS-C155B 150AH COMPACT SERIES 12V High Power/High Capacity – with integral Low Temperature Protection and Bluetooth Remote Monitoring 155AH premium lithium-iron phosphate deep cycle leisure battery featuring an ultra compact footprint of the 100 and 120 super series batteries. Bluetooth...

www.ksenergy.co.uk

It is 330 x 170 x 215 LxWxH

LA80 without the cover is 315 x 175 x 190

I already have 200W solar, with a Victron MPPT, and a Victron 30a B2B. Both these have lithium profiles. I'll keep the factory mains charger for now, as it seems like a big job to get to it.

KS-Energy say they fit them quite often in T6s on their side, and the factory mains charger with an AGM profile will be fine - the BMS will stop charging at the correct voltage.

Anyone fitted one, or got any reason not to get one? The 150AH capacity is very attractive.

Cheers.

 

[a892374923874]

No-one got any opinions?!

 

[CALI FATE]

i remember seeing a previous thread on this - maybe try a search - i would be interested in a similar upgrade on my Beach - there were concerns about potential fire hazard ?

 

[CALI FATE]

Lithium LifePo4 12v Batteries - Time For An Upgrade?

Lithium Batteries are the future, (keep checking back for the latest news/edits) ************************************************** Dellmassive`s -- "how I Done It" -- Thread ************************************************** Kit List And Stuff -- How I Done It & What I Use --...

www.t6forum.com

 

[Kayleigh]

If you have the MPPT and split charger you are pretty much set, but with 200w of solar do you really need to upgrade?

If you do, maybe check the Roamer seat base battery at 230ah for about £200 more. It’s designed to fit under the T6 front seat.

 

[Kayleigh]

i remember seeing a previous thread on this - maybe try a search - i would be interested in a similar upgrade on my Beach - there were concerns about potential fire hazard ?

LiFePO4 are safe.

 

[calibusje]

For your information, what I found about lithium batteries (also called LiFePO4): currently they are expensive. There are of course pros: much lighter (can be important) and can be completely discharged (maximum capacity to be used), recharge faster and are completely maintenance-free. Also a much longer life. Do they have any disadvantages (besides the high price then)? Yes, they cannot deliver such high discharge currents, so no inverters of, for example, 3000 watts / 250 A (for us no problem, no need for that). This shortens the lifespan but can also cause them to ignite! (Chemical fire and difficult to extinguish). For that you need a Battery Management System (BMS) to monitor the cell voltages, temperature and alarm status that shuts down users and stop the charging process when the temperature of a cell gets too high (this should be ok with the setup they said to you). Maybe not so common but they can also freeze: you can still use them, but you can only charge them above freezing point and that is not really convenient. I'm still in favor of them, but I know that they aren't an all-encompassing solution either, I don't want to glorify them, not yet but they could become an ideal solution. Good household batteries, possibly supplemented with solar panels, are of course also possible. I'll follow and see.
Greetings

 

[Nand0]

For your information, what I found about lithium batteries (also called LiFePO4): currently they are expensive. There are of course pros: much lighter (can be important) and can be completely discharged (maximum capacity to be used), recharge faster and are completely maintenance-free. Also a much longer life. Do they have any disadvantages (besides the high price then)? Yes, they cannot deliver such high discharge currents, so no inverters of, for example, 3000 watts / 250 A (for us no problem, no need for that). This shortens the lifespan but can also cause them to ignite! (Chemical fire and difficult to extinguish). For that you need a Battery Management System (BMS) to monitor the cell voltages, temperature and alarm status that shuts down users and stop the charging process when the temperature of a cell gets too high (this should be ok with the setup they said to you). Maybe not so common but they can also freeze: you can still use them, but you can only charge them above freezing point and that is not really convenient. I'm still in favor of them, but I know that they aren't an all-encompassing solution either, I don't want to glorify them, not yet but they could become an ideal solution. Good household batteries, possibly supplemented with solar panels, are of course also possible. I'll follow and see.
Greetings

Some observations, based on my own research:

LiFePO4 are one type of Lithium batteries, which as Kayleigh above says are safe in the sense that they will not combust if pierced

Realistically, anyone aiming to pull 250A from a leisure battery will have/should have a bank of batteries, not a single one. The inverter in the Cali is 300w I believe, so 25A. I haven't seen a 12v LiFePO4 battery that doesn't let you pull 25A continuously. You can get batteries with 280A cells that will let you pull 280A, but again, if you want to pull that much current, you need to look into using several batteries in parallel (and budget for some expensive fat cables)

You really really want a battery with a BMS, or else your battery will most likely die a premature death

You can get batteries with heating elements that will let you charge in sub-zero temperatures. Otherwise, you can always switch on the diesel heater to get the battery above zero I suppose

If you know a bit about electrics, you can build your own. It's not actually very hard, and there's plenty of info online. I built a 100ah battery (about 95ah real) for camping purposes for under 400 Sterling. But if you are not into that sort of thing, best to buy a ready made one with a built in BMS.

Finally, the charging of Lithium batteries is different to charging AGM batteries. If you hook up a LiFePO4 battery directly in place of the old AGM, you will have problems getting it charged. You will likely kill your battery in short order unless the BMS is smart enough to prevent charging with an AGM profile. You'd want to look into something like a DC-DC charger designed for Lithium batteries to add on top.

 

[calibusje]

Some observations, based on my own research:

LiFePO4 are one type of Lithium batteries, which as Kayleigh above says are safe in the sense that they will not combust if pierced

Realistically, anyone aiming to pull 250A from a leisure battery will have/should have a bank of batteries, not a single one. The inverter in the Cali is 300w I believe, so 25A. I haven't seen a 12v LiFePO4 battery that doesn't let you pull 25A continuously. You can get batteries with 280A cells that will let you pull 280A, but again, if you want to pull that much current, you need to look into using several batteries in parallel (and budget for some expensive fat cables)

You really really want a battery with a BMS, or else your battery will most likely die a premature death

You can get batteries with heating elements that will let you charge in sub-zero temperatures. Otherwise, you can always switch on the diesel heater to get the battery above zero I suppose

If you know a bit about electrics, you can build your own. It's not actually very hard, and there's plenty of info online. I built a 100ah battery (about 95ah real) for camping purposes for under 400 Sterling. But if you are not into that sort of thing, best to buy a ready made one with a built in BMS.

Finally, the charging of Lithium batteries is different to charging AGM batteries. If you hook up a LiFePO4 battery directly in place of the old AGM, you will have problems getting it charged. You will likely kill your battery in short order unless the BMS is smart enough to prevent charging with an AGM profile. You'd want to look into something like a DC-DC charger designed for Lithium batteries to add on top.

All true, what I said also (yes, LifePO4 is a type but it’s the one most referred to, known & installed, that’s why I took this name). I would certainly recommend have it installed by a professional.

 

[Kayleigh]

Of course another option is to go for a portable LiFePO4 power station. One that can be charged by mains, 12v or solar. Has the added flexibility that you can use it outside the van. I’m also considering this and a portable folding solar panel.

 

[California_Ocean]

Get one with a built in BMS.
Get one with an in-built heater so they can always be charged.
Use Lithium charge profiles in your DC-DC and Solar chargers.
Put the DC-DC between the VW charger (Which will have an AGM profile)/vehicle alternator and the Li battery.

It is a good idea to put a DC-DC converter between the alternator and the Li battery. Li batteries can draw huge currents when charging which may well cook the alternator - check the batteries max charging current against the alternator spec - the problems happen when the alternator is spinning at idle speeds - they don't cool so well because the fan speed is related to engine speed - every wondered why the "Max Charge" function in the CU raises the idle speed? A DC-DC converter will limit the charge current the LI battery can draw. The VW charger will also be using an AGM charge profile, the DC-DC will step this up to Li charge voltages and keep your Li battery happy.

Have a look here at a rather ott victron van ... the principles are the same even with smaller installs.

The Victron Van install - Victron Energy

The Victron Van is an installation comprising the following Victron Energy products, with videos and schematics to show how they all fit together: a MultiPlus Compact with occasional grid connection, Isolation Transformer, VE.Bus BMS Mains detector, Battery Protects, Buck-Boost DC-DC Converter...

www.victronenergy.com

 

[California_Ocean]

Get one with a built in BMS.
Get one with an in-built heater so they can always be charged.
Use Lithium charge profiles in your DC-DC and Solar chargers.
Put the DC-DC between the VW charger (Which will have an AGM profile)/vehicle alternator and the Li battery.

It is a good idea to put a DC-DC converter between the alternator and the Li battery. Li batteries can draw huge currents when charging which may well cook the alternator - check the batteries max charging current against the alternator spec - the problems happen when the alternator is spinning at idle speeds - they don't cool so well because the fan speed is related to engine speed - every wondered why the "Max Charge" function in the CU raises the idle speed? A DC-DC converter will limit the charge current the LI battery can draw. The VW charger will also be using an AGM charge profile, the DC-DC will step this up to Li charge voltages and keep your Li battery happy.

Have a look here at a rather ott victron van ... the principles are the same even with smaller installs.

The Victron Van install - Victron Energy

The Victron Van is an installation comprising the following Victron Energy products, with videos and schematics to show how they all fit together: a MultiPlus Compact with occasional grid connection, Isolation Transformer, VE.Bus BMS Mains detector, Battery Protects, Buck-Boost DC-DC Converter...

www.victronenergy.com

As I'm not a VIP member I was unable to edit the bollox I wrote above. Please read

"The VW charger will also be using an AGM charge profile, the DC-DC will step this up to Li charge voltages and keep your Li battery happy."

to ....

"The VW charger will also be using an AGM charge profile, the DC-DC will control the voltage to the narrower tolerance of Li batteries, use a proper Li charge profile and keep your Li battery happy."

 

[a892374923874]

If you have the MPPT and split charger you are pretty much set, but with 200w of solar do you really need to upgrade?

If you do, maybe check the Roamer seat base battery at 230ah for about £200 more. It’s designed to fit under the T6 front seat.

Reason for upgrade is that the original gives me approx 400Wh usable. By the time I've charged up tablets, phones, Kids' RC cars, drone batteries a couple of times, especially if doing this towards the end of the day as the solar dies off, there's not enough power to run the heater overnight. The new battery would give me 1200Wh usable even treating it kindly and keeping it in the range of 20% to 80%.

I looked at that roamer battery, but didn't want to take up the whole driver underseat area. I'd rather use the existing battery area.

other posts

I already have DC-DC charger in place, and a Victron battery protect, and the linked battery has a BMS, which will also prevent charging below freezing so I think all is good. I don't think I need a battery heater, the internal temp is unlikely to be below freezing when the van is in use.

If you know a bit about electrics, you can build your own. It's not actually very hard, and there's plenty of info online. I built a 100ah battery (about 95ah real) for camping purposes for under 400 Sterling. But if you are not into that sort of thing, best to buy a ready made one with a built in BMS.

Ah, that's interesting - I guess there are forums covering this? Can you point to any threads to get me started?

 

[clarinetbcn]

Reason for upgrade is that the original gives me approx 400Wh usable. By the time I've charged up tablets, phones, Kids' RC cars, drone batteries a couple of times, especially if doing this towards the end of the day as the solar dies off, there's not enough power to run the heater overnight. The new battery would give me 1200Wh usable even treating it kindly and keeping it in the range of 20% to 80%.

I looked at that roamer battery, but didn't want to take up the whole driver underseat area. I'd rather use the existing battery area.


I already have DC-DC charger in place, and a Victron battery protect, and the linked battery has a BMS, which will also prevent charging below freezing so I think all is good. I don't think I need a battery heater, the internal temp is unlikely to be below freezing when the van is in use.


Ah, that's interesting - I guess there are forums covering this? Can you point to any threads to get me started?

Lithium LifePo4 12v Batteries - Time For An Upgrade?

@Mike23864 & @T6ChrisO Yes thats correct. . . you can run for double the run time with Lithium vs SLA (AGM/EFB etc) this is due to you only being able to use the top 50% of the capacity of SLA batteries. with lithium you can use 100% of the capacity is you wish. ++++++++ another benefit...

www.t6forum.com

 

[Nand0]

Ah, that's interesting - I guess there are forums covering this? Can you point to any threads to get me started?

Just search Google or Youtube for something like "diy 12v camping battery"

I sourced most of the parts through Aliexpress. They are sold as 100ah B grade cells. I tested them individually and the lowest capacity one gave me 94.6ah. Cells and a BMS are the most important parts. The rest are either small parts (cables, connectors, etc) or tools you may need/want to build the battery (I bought a tester, I already had an adjustable power supply, etc...)

 

[Kayleigh]

My suggestion was as a replacement under the passenger seat rather than an additional battery under the drivers seat.

I looked at that roamer battery, but didn't want to take up the whole driver underseat area. I'd rather use the existing battery area.

 

[a892374923874]

Thanks for the pointer to the DIY batteries. Interesting reading. I'll stick with a commercial one this time around.

I'd rather have the battery permanently installed rather than a portable option.

I've taken the passenger seat off and removed the original battery to have a look. Conclusions so far:-

1. The Roamer seat base battery won't fit under the passenger seat. It is too deep and too wide. Height is ok. It should fit under the driver seat though.
2. The 150Ah KS Energy battery might fit sideways, but it is too wide and deep for the existing battery tray without mods.
3. There is a 125Ah version that will fit in the tray as is, but it is 15mm higher than the existing battery. I think this will be ok, but need to do another check against the bottom of the seat at full forward and backwards positions.
4. The Renogy and TNpower batteries are lower capacity, and too wide and deep to fit in the tray without mods.

 

[Rich20]

Thanks for the pointer to the DIY batteries. Interesting reading. I'll stick with a commercial one this time around.

I'd rather have the battery permanently installed rather than a portable option.

I've taken the passenger seat off and removed the original battery to have a look. Conclusions so far:-

1. The Roamer seat base battery won't fit under the passenger seat. It is too deep and too wide. Height is ok. It should fit under the driver seat though.
2. The 150Ah KS Energy battery might fit sideways, but it is too wide and deep for the existing battery tray without mods.
3. There is a 125Ah version that will fit in the tray as is, but it is 15mm higher than the existing battery. I think this will be ok, but need to do another check against the bottom of the seat at full forward and backwards positions.
4. The Renogy and TNpower batteries are lower capacity, and too wide and deep to fit in the tray without mods.

Just a note of caution with point 3. Check that the Airbag cable under the seat doesn’t snag, it can very easily be damaged as it’s quite flimsy.

 

[a892374923874]

Good point on the airbag cable.

I think the 125aH battery is the only drop in replacement I've come across.

KS-C125B 12v 125AH Compact Series Bluetooth lithium leisure battery - KS Energy UK

KS-C125B 125AH COMPACT SERIES 12V High Density – with integral Low Temperature Protection and Bluetooth Remote Monitoring 125AH lithium-iron phosphate deep cycle leisure battery featuring an high density ultra compact footprint of 305mm*170mm*205mm (smaller than KS-LT100/LT120B). Bluetooth...

www.ksenergy.co.uk

It is 305 x 170 x 205 LWH and should drop straight into the tray.

There is 30mm above the (190mm) existing battery height before it snags the rear seat bar, so the 205mm battery should be fine and give enough room for the airbag & seat heater cables. The terminals are on top of the 205mm, so I've got 15mm to play with, including some protection.

 

[a892374923874]

Took the opportunity to make a tray for the circuit breaker, Battery Protect, Smart Shunt and additional fuse box and tidy up all the wiring.

Used a bit of aluminium flat bar left over from making a slideout tray.

Here it is all shaped, drilled and tapped, and a test fitting. The smartshunt is mounted on the underneath of the bar, below the fusebox. Hopefully fit it tomorrow after a quick coat of paint.

 

[a892374923874]

An update.

I ordered the 125Ah battery. It is 5mm taller than the specs which stated 205mm, which means there isn't enough clearance (just) for it to fit on the battery tray in normal orientation.

So, I've installed it on it's side. As it has a wider footprint than the battery tray, I've added a piece of 9mm OSB to the battery tray which brings the base of the battery level up above the lips on the tray.

As an alternative I could get a new battery tray which doesn't have the lips, but no need for now.

• The Smartshunt is mounted on the underside of the metal bar underneath the fusebox.
  
  
• The Solar MPPT unit is in the boot cubby hole where the jack is.
  
  
• The DC-DC charger is under the driver's seat - it connects back into where the split charge relay was located via a gutted relay housing shown in the photo.
  
  
• The black rocker switch in upper middle left part of the photo is the remote on/off for the battery protect. When we're not using the van we just reach under the seat and knock that switch off, and all the loads are removed.

Here's it all back together again. I still need to find a way of clamping the battery in place.




I also fitted a couple of 50A connectors under the driver seat last year. The grey one is connected "after" the battery protect via a fuse and used for drone, rc/car charging etc. The red one is connected "before" the battery protect (but after the 60A circuit breaker) and can be used for charging the leisure battery, or for an inverter. There were convenient bolt holes already in the seat base, and the height of the connector *just* allows the seat bar to pass over it when the seat is fully forward.

 

[MattBW]

How are you getting on with the setup? Very interesting setup.

 

[a892374923874]

All ready to go, just waiting to go on a longer trip to see how it all works for real. I think power will cease to be a problem.

The mains charger (original VW) keeps charging until the BMS stops overcharging at 14.7v. The BMS is therefore working as designed. But then, the battery voltage decays down a bit, the BMS re-enables charge, and the charge starts again.

I don't expect to use the mains charger much at all, and when I do I'll just pull the blade fuse when it is reasonably charged. I'd replace the charger with a Victron, but I don't really want to pull all the plastic trim off to get at it.

Ideally the battery should be used between 20% and 80%, and at 60% if being stored. I'm experimenting with what charge cutoff voltage equates to around 80%. Normal cutoff for 100% is 14.4v to 14.6v

I've also added a wifi router, and a Raspberry Pi running Victron Venus OS which then provides web based monitoring of the Victron battery shunt and the solar controller. The router, and Pi in a case sits on top of the battery, and they clear the seat base.

On the left hand side of the battery in the photo there's enough space to put an Odroid HC2 which has a 1TB SSD. The Odroid is similar to a Pi, and runs Plex, so the kids can watch movies via wifi from their tablets without needing the internet.

 

[stim]

@a892374923874 did you ever end up replacing the factory EHU AGM charger in your beach?

 

[Hueyhew]

This battery on its side almost exactly matches the dimensions of the rubber cover over the Varta LA80 under my 2019 Beach passenger seat.

KS-C155B 12v 155AH Compact Series Bluetooth High Power lithium leisure battery - KS Energy UK

KS-C155B 150AH COMPACT SERIES 12V High Power/High Capacity – with integral Low Temperature Protection and Bluetooth Remote Monitoring 155AH premium lithium-iron phosphate deep cycle leisure battery featuring an ultra compact footprint of the 100 and 120 super series batteries. Bluetooth...

www.ksenergy.co.uk

It is 330 x 170 x 215 LxWxH

LA80 without the cover is 315 x 175 x 190

I already have 200W solar, with a Victron MPPT, and a Victron 30a B2B. Both these have lithium profiles. I'll keep the factory mains charger for now, as it seems like a big job to get to it.

KS-Energy say they fit them quite often in T6s on their side, and the factory mains charger with an AGM profile will be fine - the BMS will stop charging at the correct voltage.

Anyone fitted one, or got any reason not to get one? The 150AH capacity is very attractive.

Cheers.

The on board charger probably can't fully utilise the lithium battery capability but that isn't a big issue when you're on hookup. I don't know if the on board unit has a desulphation mode but this can destroy a lithium battery. Lifepo4 also don't like to charge or discharge below zero Celsius so ideally have a temperature sensor to control this, some more expensive lifepo4 batteries have heating mats built in to manage this.