Lithium battery?

[ferret50]

I currently have a 100AH deep cycle lead acid battery that I have used in three vans over the last seven or eight years.

Load is mostly a Domtec fridge, bit of lighting, phone/laptop and the power side of a diesel heater.

Modest solar panel/MPPT controller and a battery to battery charger.

Usage is mostly two, two monthish trips UK/Algarve, perhaps 3k miles round trips.

I'm thinking of this.....

https://www.tayna.co.uk/leisure-batteries/sterling...

...as a replacement battery to buy/install this summer. This is a significant cost, am I daft/crazy or should I buy two 100AH lead acid replacements?

[Mr Pointy]

What's wrong with your current battery that's driving you to replace it & what is the cost difference? I'm not a battery expert but LiPO batteries make me a bit nervous. Will you need to change the charger as well?

[ferret50]

Current battery is struggling on longer nights, our last trip was Jan/April, so fridge was going off going out but just about managing for the return.

The link gives a price, but it's thick end of £500, two lead acid would be about half that. Charging system will cope with either setup, but the litium would take up less room, leaving more for hiding hooch!

[peterperkins]

That's a safer Lithium Iron Phosphate battery not a LiPo.

[jfdi]

What are you gaining other than a bit of space and a weight reduction. 100 amp hours is 100 amp hours regardless of the chemistry. 2x100amp hour lead acid batteries will last twice as long and be half the price. You must really need the space or weight saving to justify it.

[s2sol]

jfdi said:

What are you gaining other than a bit of space and a weight reduction. 100 amp hours is 100 amp hours regardless of the chemistry. 2x100amp hour lead acid batteries will last twice as long and be half the price. You must really need the space or weight saving to justify it.

100Ah of lead acid gives you about 50Ah of useable capacity. 100Ah of lithium will give about 80-90Ah of useable capacity. This is the ideal use case for a drop in replacement.
Fogstar do a 105Ah battery for a fair bit less than the linked one from Tayna. I've got a 460Ah Fogstar, and it's been a game changer.

Edited by s2sol on Sunday 2nd June 17:13

[ferret50]

s2sol said:

jfdi said:

What are you gaining other than a bit of space and a weight reduction. 100 amp hours is 100 amp hours regardless of the chemistry. 2x100amp hour lead acid batteries will last twice as long and be half the price. You must really need the space or weight saving to justify it.

100Ah of lead acid gives you about 50Ah of useable capacity. 100Ah of lithium will give about 80-90Ah of useable capacity. This is the ideal use case for a drop in replacement.
Fogstar do a 105Ah battery for a fair bit less than the linked one from Tayna. I've got a 460Ah Fogstar, and it's been a game changer.

Edited by s2sol on Sunday 2nd June 17:13

This one?

https://www.fogstar.co.uk/collections/lithium-leis...

Yes, it is the usable capacity that is a lot of the attraction, any idea on how long these last, please?

[s2sol]

ferret50 said:

This one?

https://www.fogstar.co.uk/collections/lithium-leis...

Yes, it is the usable capacity that is a lot of the attraction, any idea on how long these last, please?

That's the one. I couldn't say, I've only had mine eight months, but I live full time in the van, so it gets some use. According to the app, it's done 9 charge cycles in that time. Life expectancy is 300-500 cycles, so I'm guessing at about one a month, it'll see me out.

[ferret50]

s2sol said:

That's the one. I couldn't say, I've only had mine eight months, but I live full time in the van, so it gets some use. According to the app, it's done 9 charge cycles in that time. Life expectancy is 300-500 cycles, so I'm guessing at about one a month, it'll see me out.

Thanks for your help.

Fulltiming?

I'm afraid that I would miss my home workshop, but I admire those who can cope with the limited space.

[s2sol]

ferret50 said:

Thanks for your help.

Fulltiming?

I'm afraid that I would miss my home workshop, but I admire those who can cope with the limited space.

Sold the house two years ago and never got around to buying another one! Sixteen countries ticked off so far.

[Spuffington]

I have a 95aH LiFePo4 battery in my Knaus BoxDrive. I got it as part of the deal with Premium Motorhomes at the time of purchase. I suspect they had a few smaller units lying around they were trying to shift. I was initially nervous about not having significantly more amps available. However, after 1yr and c. 35 overnights, in some pretty rubbish & cold weather too, I can confirm it's sufficient. The key thing is the B2B charger which brings it back to full capacity within 30mins of driving.

For me, it's not sufficient for more than one night of wilding in very cold weather but it has enough redundancy that I know the lights / heating won't be going off during the night. It's also strong enough to run 2-4 Nespresso drinks in the morning via the 2kw inverter.

I have considered upgrading it, but would only do so if I knew I was spending 2-3nights stationary but my typical tendency is to move around on a daily basis.

HTH

[ferret50]

Thanks Spuffy, your LiFoPO4 comes in at £240, whilst brousing they offered me a new customer £10 voucher!

The Fogstar offering is £370, so my selection from Tayna at around £500 delivered does look pricey.

Yet again, knowlegable PH'ers have delivered.

Any more? This is the next purchase after a new clutch, booked in for next week.

[silentbrown]

s2sol said:

Life expectancy is 300-500 cycles, so I'm guessing at about one a month, it'll see me out.

More like 3500 cycles. 10 year warranty on the Fogstar one, for example.

[s2sol]

silentbrown said:

More like 3500 cycles. 10 year warranty on the Fogstar one, for example.

Fantastic, it'll definitely see me out. I suspect, because I've got 460Ah, it'll be very rare that I use more than about half the capacity, so it should last many, many years.
It took a few weeks before I had faith in it, but it runs a little air fryer no problem. I leave the inverter switched on overnight now, too. It really has changed the way I use the van.

[Spuffington]

ferret50 said:

Thanks Spuffy, your LiFoPO4 comes in at £240, whilst brousing they offered me a new customer £10 voucher!

The Fogstar offering is £370, so my selection from Tayna at around £500 delivered does look pricey.

Yet again, knowlegable PH'ers have delivered.

Any more? This is the next purchase after a new clutch, booked in for next week.

Great news!

Like I say, I was sceptical but it sounds like your usage is very similar to mine (fridge, charging phones, diesel heater etc) and with the B2B and a bit of solar, you should have no problems. If I were fulltiming and more stationary, I'd definitely go for more. But then again, I had 300aH gel in my Concorde with 2kw inverter, an old solar panel, no B2B and Alde wet heating and managed ok most of the time. If you extrapolate 50% of that capacity as usable, it wasn't a whole lot more than I have currently with the LiFePo4.

Enjoy and good luck with the clutch! Then it's full on motoring....

[s2sol]

ferret50 said:

Thanks Spuffy, your LiFoPO4 comes in at £240, whilst brousing they offered me a new customer £10 voucher!

The Fogstar offering is £370, so my selection from Tayna at around £500 delivered does look pricey.

Yet again, knowlegable PH'ers have delivered.

Any more? This is the next purchase after a new clutch, booked in for next week.

I used to have a business repairing motorhomes, and I used Tayna or Battery Megastore for replacement batteries. Tayna's customer service is excellent. Battery Megastore was local, and they gave me good trade prices.
I think you'll be delighted with the increase in useable capacity wherever you buy from. Keep the thread updated, I'd be fascinated to hear how you get on with it.

[ferret50]

s2sol said:

I used to have a business repairing motorhomes, and I used Tayna or Battery Megastore for replacement batteries. Tayna's customer service is excellent. Battery Megastore was local, and they gave me good trade prices.
I think you'll be delighted with the increase in useable capacity wherever you buy from. Keep the thread updated, I'd be fascinated to hear how you get on with it.

Thanks, I've ordered as the discount woucher was only valid for three days, but I'll try to detail installation and how I get along with it.

[Sandy0728]

Just to put my limited experience into the mix;

We have a touring caravan and have previously used lead acid. The original old Avondale used to kill batteries for fun over winter due to the alarm draining them down, and us not keeping on top of visiting the storage to charge/replace the battery.
The replacement Coachman stayed with us for 3 years with the benefit of a solar panel which kept the battery topped up over winter. This went through 1 battery but this was not a new one (carried over from the previous unit).
We are now 3 months into the latest Coachman which replaced the previous unit that was written off.
I spent a lot of time researching opinions on lithium when used with a touring caravan vs Lead.
Not that much info out there really or actual experience that I could see.
Plenty of negative opinions from forums about them but non that were based on actual experience.

I visited the NEC and spoke to numerous suppliers both lead and lithium. The lead suppliers were understandably negative about lithium stating not suitable for motor movers etc.
Lithium suppliers said simply no reports of any issues, but I did not find any actual examples to back this up.

In the end after doing my home work, I made sure the solar charger (Truma) was suitable for lithium. It was & I just need to change the settings to match the battery type.
Also the factory charger needs to be compatible with lithium, which it is and stated in the owners handbook. It just stipulates that the battery must have its own built in BMS.

I ended up with a Fogstar 105 battery which has a BMS, bluetooth monitoring & switching as well as heating element.
This choice was mainly due to the price, but also I was reassured with the fact that they are not just buying a battery and re-branding it - which is pretty common.
The built in heater is a bonus as we camp all year round.

We've currently only had the new unit for around 3 months fitted with the battery from the start. Its working fine so far. Holding charge when in storage (with solar panel).
The new van is the largest yet at 1.9 T max. It has double motor movers and E&P levelling system.
We are not heavy users of the motor movers (I can reverse it onto a pitch faster than I can use the movers), but have used them a couple of times.
We also had one sloped pitch which meant we used the E&P system around 4 times in a row until it was fully levelled (newby mistakes!).
We've not seen the battery drop more than 5% during the above usage.
We've only done one night 'off-grid' so far with no issues.

Still early days for us, but I'm happy with it so far. The 10kg weight saving is also helpful!

Not much of a user review, but more the thoughts that went into my choice. Hopefully some help to somebody.

Sandy.

[Russ T Bolt]

I had 2 x 160ah AGM batteries in my motorhome that were quite old and running at about 60%.

I had them replaced with a 460ah lithium battery in April. works really well and saves about 70kg in weight.

[ferret50]

I'm sorry it's taken so long to get back to this with a few photo's, but I've had both computer issues and a damaged back!



Old and new for size comparision. New is also significantly lighter.



New battery fitted and secured, that red lead with the ring goes to the master switch.

Electrics panel back in place, I can access the space to the left of the battery by removing just 4 screws, and last week I tidied the space behind the panel and above the battery with a couple of partitions to give me a further hooch storage place accessed from above by hinging the bed upwards.