Lithium battery questions

kevsbox

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I am thinking about replacing my aging leisure battery with a nice shiny 100Ah Lithium battery such as the 12V 100Ah LiFePO4 Lithium Battery at uk.eco-worthy.com.

But first a few questions
  • Any thoughts on the best one to use? Any I should avoid?
  • I have recently replaced the starter with a Hankook XL31. These will share a common negative, will this be a problem?
  • Charging from the solar panel is controlled by a Marlec HRDi, can these safely charge Lithium batteries or will I need to change that also?
Any thoughts please
 

fredrussell

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Others will explain why, I’m sure, but be aware it will not be a simple ‘drop in’ replacement. Those eco-worthy batteries seem to have a good rep - my friend has just installed one - but be aware that cheaper lithium batteries might not have as good a BMS as more expensive ones. It’s an important difference!
 

kevsbox

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Others will explain why, I’m sure, but be aware it will not be a simple ‘drop in’ replacement. Those eco-worthy batteries seem to have a good rep - my friend has just installed one - but be aware that cheaper lithium batteries might not have as good a BMS as more expensive ones. It’s an important difference!
I had a feeling that would be said, there is also a price to pay when going for the cheapest.
 

geem

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I am thinking about replacing my aging leisure battery with a nice shiny 100Ah Lithium battery such as the 12V 100Ah LiFePO4 Lithium Battery at uk.eco-worthy.com.

But first a few questions
  • Any thoughts on the best one to use? Any I should avoid?
  • I have recently replaced the starter with a Hankook XL31. These will share a common negative, will this be a problem?
  • Charging from the solar panel is controlled by a Marlec HRDi, can these safely charge Lithium batteries or will I need to change that also?
Any thoughts please
It's nothing like a simple as dropping a lithium battery in. You will need to satisfy your insurer that the installation is sound. This will normally mean proffessional installation or sign off from a proffessional marine electrician. A marine electrician will assess the installation again a known standard for lithium such as the Amercian ABYC. Things you need to consider are installation of a class T fuse as close to the lithium battery as possible. A smart shunt to monitor the amps in and our of the lithium accurately. Intelligent solar controllers that can use the smart shunt to stop charging before the lithium battery decides to do a shut down. Otherwise at this point you would lose navigation lights, instruments, autopilot, fridge, etc. You need to either install a smart regulator to your alternator if you intend to charge the lithium with it or no longer charge the lithium with an alternator. You can add a B2B charger to charge lithium from the engine battery.
There is far more to consider than just dropping in a lithium battery.
 
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kevsbox

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It's nothing like a simple as dropping a lithium battery in. You will need to satisfy your insurer that the installation is sound. This will normally mean proffessional installation or sign off from a proffessional marine electrician. A marine electrician will assess the installation again a known standard for lithium such as the Amercian ABYC. Things you need to consider are installation of a class T fuse as close to the lithium battery as possible. A smart shunt to monitor the amps in and our of the lithium accurately. Intelligent solar controllers that can use the smart shunt to stop charging before the .ithium battery decides to do a shut down. Otherwise at this point you would lose navigation lights, instruments, autopilot, fridge, etc. You need to either install a smart regulator to your alternator if you intend to charge the lithium with it or no longer charge the lithium with an alternator. You can add a B2B charger to charge lithium from the engine battery.
There is far more to consider than just dropping in a lithium battery.
Wow, that is a lot to consider
 

ibbo

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The solar controller wouldn't appear to be suitable, 14.4 Bulk, and 13.8 float from the manual.
Common earth is no problem, indeed necessary.

The alternator may not like charging the Lithium either. I have a B2B to charge from the engine battery while it is running.

Mike
 

ckris

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I am thinking about replacing my aging leisure battery with a nice shiny 100Ah Lithium battery such as the 12V 100Ah LiFePO4 Lithium Battery at uk.eco-worthy.com.

But first a few questions
  • Any thoughts on the best one to use? Any I should avoid?
  • I have recently replaced the starter with a Hankook XL31. These will share a common negative, will this be a problem?
  • Charging from the solar panel is controlled by a Marlec HRDi, can these safely charge Lithium batteries or will I need to change that also?
Any thoughts please
Not familiar with the Eco-worthy but looks like it does not have a configurable BMS or bluetooth, also not clear how it handles temperature protection or the warranty position. I have used 2 suppliers which I have been impressed with that you may want to check out:
Life Batteries - slightly more expensive but more personalised service, they will configure the BMS for your install scenario.
Fogstar - slightly cheaper but you really should re-configure the BMS as the out of the box are not conservative settings.

There are quite a few videos on Youtube where people tear down drop in batteries, worth having a look to get an idea of what what is inside these boxes. I think it is possible to get decent quality now, but there are some poor ones as well.

There is a Facebook group "12 volt boating group" where posters collectively have a lot of experience of different drop in batteries and how to set them up.
 

geem

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Not familiar with the Eco-worthy but looks like it does not have a configurable BMS or bluetooth, also not clear how it handles temperature protection or the warranty position. I have used 2 suppliers which I have been impressed with that you may want to check out:
Life Batteries - slightly more expensive but more personalised service, they will configure the BMS for your install scenario.
Fogstar - slightly cheaper but you really should re-configure the BMS as the out of the box are not conservative settings.

There are quite a few videos on Youtube where people tear down drop in batteries, worth having a look to get an idea of what what is inside these boxes. I think it is possible to get decent quality now, but there are some poor ones as well.

There is a Facebook group "12 volt boating group" where posters collectively have a lot of experience of different drop in batteries and how to set them up.
I just had a look at the spec on those Ecworthy lithium batteries. They really are not suitable for a boat. The BMS is not even Bluetooth from what I can see. You would have no way of knowing the state of charge. They really are a crap battery for a boat and potensially dangerous.
 

kevsbox

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I just had a look at the spec on those Ecworthy lithium batteries. They really are not suitable for a boat. The BMS is not even Bluetooth from what I can see. You would have no way of knowing the state of charge. They really are a crap battery for a boat and potensially dangerous.
Thanks for the info
 

Trident

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Renogy are excellent and I’ve installed loads of them on dozens of boats

I would note that currently there is absolutely no agreed standard for electrical installation on a boat in the UK and even a detailed survey would be unlikely to note anything but the obvious errors like wires twisted together in a wet bilge as a join . Certainly in the Uk at least no insurance company would have a clue what standards to ask for on a lithium installation and who should do it. There are many competing qualifications for marine electricians and none are mandatory and none have any force in law so simply buying a quality product designed , according to the manufacturer, for your application would be all you need to do to keep insurance cover and avoid any pitfalls. What Geem says may be the case in the USA but is not an issue here and I suspect won’t be until something goes horribly wrong

There is also no need for a BMS to be Bluetooth- Renogy do both and I always recommend the non Bluetooth batteries because in their case the Smart battery which has a separate monitor for all BMS functions is actually a higher spec than the BT versions they do The key issue is being able to look at what the BMS is doing and possibly to change it

A drop in like the Renogy needs only to be fitted with no direct link to the alternator- either a DC DC charger or a simple VSR between the start battery and the LiFePo will protect the alternator. The solar controller should have a lithium setting or be programmable and the current shore power charger can be used via the DCDC or VSR from the start battery

There is more to consider with multiple batteries and better ways to ensure the maximum life span of the battery but for a single 100ah battery just get a Renogy or similar ( Fogstar are also good) and fit as above and you’ll be fine
 

geem

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Renogy are excellent and I’ve installed loads of them on dozens of boats

I would note that currently there is absolutely no agreed standard for electrical installation on a boat in the UK and even a detailed survey would be unlikely to note anything but the obvious errors like wires twisted together in a wet bilge as a join . Certainly in the Uk at least no insurance company would have a clue what standards to ask for on a lithium installation and who should do it. There are many competing qualifications for marine electricians and none are mandatory and none have any force in law so simply buying a quality product designed , according to the manufacturer, for your application would be all you need to do to keep insurance cover and avoid any pitfalls. What Geem says may be the case in the USA but is not an issue here and I suspect won’t be until something goes horribly wrong

There is also no need for a BMS to be Bluetooth- Renogy do both and I always recommend the non Bluetooth batteries because in their case the Smart battery which has a separate monitor for all BMS functions is actually a higher spec than the BT versions they do The key issue is being able to look at what the BMS is doing and possibly to change it

A drop in like the Renogy needs only to be fitted with no direct link to the alternator- either a DC DC charger or a simple VSR between the start battery and the LiFePo will protect the alternator. The solar controller should have a lithium setting or be programmable and the current shore power charger can be used via the DCDC or VSR from the start battery

There is more to consider with multiple batteries and better ways to ensure the maximum life span of the battery but for a single 100ah battery just get a Renogy or similar ( Fogstar are also good) and fit as above and you’ll be fine
My insurer is Pantaneus in the UK. I asked them the question directly and got an answer in writing. The lithium should be installed by a professional marine electrician or vetted on completion.
Other insurers may have a different view.
I installed my lithium to ABYC standard because it's sensible
ABYC Ratifies E-13, their first lithium battery standard
 
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Trident

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My insurer is Pantaneus in the UK. I asked them the question directly and got an answer in writing. The lithium should be installed by a professional marine electrician or vetted on completion.
Other insurers may have a different view.
I installed my lithium to ABYC standard because it's sensible
ABYC Ratifies E-13, their first lithium battery standard
I don't disagree but in the UK there is no legal or agreed standard - even for full commercial coding the wording on electrical is entirely vague - "to best current practice" etc - no one has any set standard and there is nothing codified about Lithium at all - this of course means its impossible for an insurer to claim best practice has not been met if they can't define it; had you bought your boat with the lithiums installed by the previous owner I would doubt your insurer would ask for any proof that they had been installed by a professional marine electrician - they would only rely at most on a survey report which would be , as they almost all are, incredibly vague on the electrical side. In the last two years I have had to correct professional qualified and experienced surveyors on multiple occasions when they have been talking about electrical installations - one even showed me a brand new installation and noted how great it was to see brand new electrics on an older boat, until I pointed out the wiring used was all undersized for the current it was being asked to carry. Another noted the battery charger on a boat he was surveying "lit up but appears not to work" - the negative lead from it wasn't even connected to the battery, or the charger!

As an aside, because of this, I have done all the work I have done professionally in the last two years to ABYC guidelines as I found them to be the most comprehensive and aligned with my own opinions - but of course they have no "standing" in the UK
 

geem

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I don't disagree but in the UK there is no legal or agreed standard - even for full commercial coding the wording on electrical is entirely vague - "to best current practice" etc - no one has any set standard and there is nothing codified about Lithium at all - this of course means its impossible for an insurer to claim best practice has not been met if they can't define it; had you bought your boat with the lithiums installed by the previous owner I would doubt your insurer would ask for any proof that they had been installed by a professional marine electrician - they would only rely at most on a survey report which would be , as they almost all are, incredibly vague on the electrical side. In the last two years I have had to correct professional qualified and experienced surveyors on multiple occasions when they have been talking about electrical installations - one even showed me a brand new installation and noted how great it was to see brand new electrics on an older boat, until I pointed out the wiring used was all undersized for the current it was being asked to carry. Another noted the battery charger on a boat he was surveying "lit up but appears not to work" - the negative lead from it wasn't even connected to the battery, or the charger!

As an aside, because of this, I have done all the work I have done professionally in the last two years to ABYC guidelines as I found them to be the most comprehensive and aligned with my own opinions - but of course they have no "standing" in the UK
The fact that you recognise the benefits of a standard such as ABYC is great. The number of times I heard people doing DIY jobs and complaining that building regulations were stupid because they made them do something they didn't want to do.
Like all standards, they are there to assist and make installations safer. There are often alternatives to the standard that are equally as safe. The more you understand the subject the easier it is the interpret the standards and maybe do things differently but still safely. The standards are often a catch all for the stupid not the educated.
 
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