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Cheap LiFePO4 BMS?


jetzi

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I think the problem with an off-the shelf system is that it would really need to replace all the charge sources or their controllers. Even the Victron system seems to require arsing about to get it to work with existing alternators. The most cost effective way to sell a system for _new_ boats is to sell a complete integrated system: alternator and reg. mains charger and solar controller, BMS and batteries. There'd just be a big fat positive cable to hang the loads on. Unfortunately for retrofit, that's an expensive do, as it involves throwing away all the existing gear. 

 

MP.

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2 hours ago, MoominPapa said:

I think the problem with an off-the shelf system is that it would really need to replace all the charge sources or their controllers. Even the Victron system seems to require arsing about to get it to work with existing alternators. The most cost effective way to sell a system for _new_ boats is to sell a complete integrated system: alternator and reg. mains charger and solar controller, BMS and batteries. There'd just be a big fat positive cable to hang the loads on. Unfortunately for retrofit, that's an expensive do, as it involves throwing away all the existing gear. 

 

MP.

That's pretty much what I said. But the cost problem isn't just for retrofit, it's also for new build, because developing and debugging such a solution and making it idiot-proof takes time and money (see Integrel) and whoever does this has to get this back (with some profit!) unless they're doing it as a hobby or for themselves, like the people on this forum are. Such a system also can't use secondhand batteries like many people are doing to keep the cost under control, the supply/reliability/capacity/lifetime/warranty issues don't allow it, so the cost of the battery packs is much higher too.

 

And now we get the chicken-and-egg problem; until enough people are willing to buy such a system nobody will bother developing and marketing it and use sales volumes to drive the price down, but until it's available cheaply enough (a long time with new batteries...) not enough people will buy it -- and even then the canal market willing to pay for an advanced battery/charging system is too small, most people don't want or need it, a few lead-acids are dirt cheap and work OK even if they die after a couple of years.

 

If the canal market is lucky it might be able to piggyback on the yacht market which is far bigger worldwide and also much richer, but the cost (with new cells) will still be a lot higher than lead-acids for the foreseeable future -- even if this evens out over (say) ten years, many people can't or won't stump up the cash up-front, or realise they're unlikely to have the same boat in ten years' time...

 

Everyone saying "but it's easy, I managed to do it like this..." has already outed themselves as somebody who understands about boat electrics and batteries (lead-acid and lithium) and charging systems and how to roll-your-own LiFePO4 solution -- which is great but you need to get out of your bubble and smell the coffee, you're one of a small minority in the canal world, for a start you're reading this ?

 

Don't get me wrong, lithium can be a great solution for some boaters, but there are many obstacles to it getting widely adopted on the canals -- it's already happening with yotties but space/weight matters to them (like cars but unlike narrowboats) and their pockets are generally much deeper...

Edited by IanD
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35 minutes ago, IanD said:

Everyone saying "but it's easy, I managed to do it like this..." has already outed themselves as somebody who understands about boat electrics and batteries (lead-acid and lithium) and charging systems and how to roll-your-own LiFePO4 solution -- which is great but you need to get out of your bubble and smell the coffee, you're one of a small minority in the canal world, for a start you're reading this ?

I think you are wrong in that it is a lot simpler than you are saying. The technology is within the grasp of a lot more than you suggest. Yes it will never be more than a small minority but I reckon 5-10% of peeps here could manage it, rather than the 0.00001% that comes over from your views. Even Richard's got Li's now! :P

Edited by Dr Bob
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22 minutes ago, IanD said:

That's pretty much what I said. But the cost problem isn't just for retrofit, it's also for new build, because developing and debugging such a solution and making it idiot-proof takes time and money (see Integrel) and whoever does this has to get this back (with some profit!) unless they're doing it as a hobby or for themselves, like the people on this forum are. Such a system also can't use secondhand batteries like many people are doing to keep the cost under control, the supply/reliability/capacity/lifetime/warranty issues don't allow it, so the cost of the battery packs is much higher too.

 

And now we get the chicken-and-egg problem; until enough people are willing to buy such a system nobody will bother developing and marketing it and use sales volumes to drive the price down, but until it's available cheaply enough (a long time with new batteries...) not enough people will buy it -- and even then the canal market willing to pay for an advanced battery/charging system is too small, most people don't want or need it, a few lead-acids are dirt cheap and work OK even if they die after a couple of years.

 

If the canal market is lucky it might be able to piggyback on the yacht market which is far bigger worldwide and also much richer, but the cost (with new cells) will still be a lot higher than lead-acids for the foreseeable future -- even if this evens out over (say) ten years, many people can't or won't stump up the cash up-front, or realise they're unlikely to have the same boat in ten years' time...

 

Everyone saying "but it's easy, I managed to do it like this..." has already outed themselves as somebody who understands about boat electrics and batteries (lead-acid and lithium) and charging systems and how to roll-your-own LiFePO4 solution -- which is great but you need to get out of your bubble and smell the coffee, you're one of a small minority in the canal world, for a start you're reading this ?

 

Don't get me wrong, lithium can be a great solution for some boaters, but there are many obstacles to it getting widely adopted on the canals -- it's already happening with yotties but space/weight matters to them (like cars but unlike narrowboats) and their pockets are generally much deeper...

I agree in some ways but realistically in a few years electric boats will be taking over and thongs will change quickly for all of us even the early adaptors 

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2 hours ago, MoominPapa said:

I think the problem with an off-the shelf system is that it would really need to replace all the charge sources or their controllers. Even the Victron system seems to require arsing about to get it to work with existing alternators. The most cost effective way to sell a system for _new_ boats is to sell a complete integrated system: alternator and reg. mains charger and solar controller, BMS and batteries. There'd just be a big fat positive cable to hang the loads on. Unfortunately for retrofit, that's an expensive do, as it involves throwing away all the existing gear. 

 

MP.

 

What you are describing is pretty much the Tesla Powerwall.  13.5kWh in a box that gets fed mains power and gives it you back on demand.  All the complicated stuff happens in a sealed box and is invisible to the end user, and you can daisychain up to 10 of them.

 

I don't know how efficient it would be if you also had to be able to feed it 12v/24v from an alternator, but it would be fine off a travelpower.  Sadly they explicitly say they are not suitable for boats. :(

 

https://www.tesla.com/en_gb/powerwall

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16 minutes ago, peterboat said:

I agree in some ways but realistically in a few years electric boats will be taking over and thongs will change quickly for all of us even the early adaptors 

I'm I pretty much a supporter of leading edge stuff but I have not taken to wearing a thong yet.

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4 hours ago, Dr Bob said:

I think you are wrong in that it is a lot simpler than you are saying. The technology is within the grasp of a lot more than you suggest. Yes it will never be more than a small minority but I reckon 5-10% of peeps here could manage it, rather than the 0.00001% that comes over from your views. Even Richard's got Li's now! :P

I didn't say it was difficult for the likes of you and me, I said it was difficult for *most* people -- and you've just agreed with me. If you multiply the 5% or so of people who *could* do it (I think 10% is optimistic going by the number of electrickery newbies on canal forums) by the (my guess) 20% of people who *want* a high-capacity battery/mains system on their boat, you get 1% of canal boaters. That's a tiny market by any measure, and is what I meant -- your guess of 0.00001% is 5 orders of magnitude out, as an engineer I'd say that's quite a long way off ?

4 hours ago, peterboat said:

I agree in some ways but realistically in a few years electric boats will be taking over and thongs will change quickly for all of us even the early adaptors 

Agreed, because it will then be the mass market not a tiny minority -- and I'm very much looking forward to silent non-polluting boats with a system-wide charging network which is what will have to happen ?

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Ive only ever been on one electric boat, a trip boat.

 

It was a quite impressive experience, the ability to hear everything on the river was fantastic.

 

Of course to achieve that it had to go on charge between trips and overnight meaning the concept has some considerable way to go.

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I'm looking forward to when someone decides to package up an electric drive and LFP battery system as a "drop in" replacement for existing diesel units. Take care of propulsion and domestic electrickery in one go. 

 

That would be pretty cool. But would obviously require a somewhat better charging network IF the batteries were to be fixed... Which is not necessary...

 

It seems to me more sensible to follow the Nio electric car model by swapping out the batteries. 

 

We've been buying packaged energy for years in the form of bottled gas. Why not do the same with batteries ? 

 

I realise batteries are consumables but with the fantastic life span being advertised and the continued reduction in grams per kWh at some point it will become the most sensible way to proceed.

 

You stop at the boatyard and instead of bunkering diesel you load a battery pack or two depending on your projected traveling. 

 

We'll get restored workboats with special "Heritage diesel engine certificates" delivering charged battery packs to boaters on the cut and taking back the depleted ones to their depots where they can be recharged for the next customer.

 

:)

 

Edited by magnetman
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34 minutes ago, magnetman said:

I'm looking forward to when someone decides to package up an electric drive and LFP battery system as a "drop in" replacement for existing diesel units. Take care of propulsion and domestic electrickery in one go. 

 

That would be pretty cool. But would obviously require a somewhat better charging network IF the batteries were to be fixed... Which is not necessary...

 

It seems to me more sensible to follow the Nio electric car model by swapping out the batteries. 

 

We've been buying packaged energy for years in the form of bottled gas. Why not do the same with batteries ? 

 

I realise batteries are consumables but with the fantastic life span being advertised and the continued reduction in grams per kWh at some point it will become the most sensible way to proceed.

 

You stop at the boatyard and instead of bunkering diesel you load a battery pack or two depending on your projected traveling. 

 

We'll get restored workboats with special "Heritage diesel engine certificates" delivering charged battery packs to boaters on the cut and taking back the depleted ones to their depots where they can be recharged for the next customer.

 

:)

 

Thankfully the battery changing thing failed for Renault and more than likely will fail for Nio, modern battery packs have heating and cooling though not really needed on boats and low power cars I suppose

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Possibly not ideal for cars because cars can be so easily positioned close to major infrastructure but on canals an electric charging system just won't happen. It's too complicated which is why portable energy is the only way to go. 

 

 

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2 minutes ago, magnetman said:

Possibly not ideal for cars because cars can be so easily positioned close to major infrastructure but on canals an electric charging system just won't happen. It's too complicated which is why portable energy is the only way to go. 

 

 

Cant see it happening I am afraid, it's up to the boaters to sort it out like I do

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47 minutes ago, magnetman said:

I'm looking forward to when someone decides to package up an electric drive and LFP battery system as a "drop in" replacement for existing diesel units. Take care of propulsion and domestic electrickery in one go. 

 

That would be pretty cool. But would obviously require a somewhat better charging network IF the batteries were to be fixed... Which is not necessary...

 

It seems to me more sensible to follow the Nio electric car model by swapping out the batteries. 

 

We've been buying packaged energy for years in the form of bottled gas. Why not do the same with batteries ? 

 

I realise batteries are consumables but with the fantastic life span being advertised and the continued reduction in grams per kWh at some point it will become the most sensible way to proceed.

 

You stop at the boatyard and instead of bunkering diesel you load a battery pack or two depending on your projected traveling. 

 

We'll get restored workboats with special "Heritage diesel engine certificates" delivering charged battery packs to boaters on the cut and taking back the depleted ones to their depots where they can be recharged for the next customer.

 

:)

 

There's no need to go to that much trouble. It would work for cars because they need much bigger battery packs (getting on for 100kWh now) and want to charge them quickly (ten minutes or so), and a 600kW charger is a challenge to say the least, which is why swappable packs are proposed (but impractical with car packaging restrictions/differences).

 

A boat would need less than half the battery capacity, and people are happier to stop for half an hour or so, maybe while they fill up the water tank -- net result, 100kW charging, which is much easier and means there's no need to swap batteries. Also avoids the risk of dropping a 100kg battery on your toe, or in the cut... 

 

The big problem is still providing the network of charging stations, but this is probably still easier than a network of battery swapping stations ?

1 minute ago, peterboat said:

Cant see it happening I am afraid, it's up to the boaters to sort it out like I do

Except your solution (huge solar array on a wideboat, hardly any travelling) doesn't meet the needs of most boaters...

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The charging stations would have to be bullet proof to avoid abuse though would they not. I don't think charging stations is going to happen. Too complicated. 

 

Battery swaps could be carried out "on the hoof" so to speak. It would become an industry like delivering diesel by boat is currently. Return to a secure base with charging infrastructure maybe even a canalside solar farm...

Obviously the systems would need to be designed to allow reasonably comfortable battery changing without needing steel toe caps. 

 

I can't help noticing rapid advances in the weight and size ie power density of batteries. 

Yes they are still heavy but boats need so little power to propel them and batteries are getting lighter by the hour apparently

ETA they are even talking about 1kwh per killergran.

 

A narrow boat must be about 2kw on an efficient electric drive system so 2kg of batteries per hour doesn't seem to be too terrible.

 

Current batteries seem to be about ten times heavier but time has a funny habit of sorting these things out. 

 

Imagine if you could buy a 13kg bottle of batteries and get a day's boating out of it then exchange for a new one. That might catch on. With your own battery as well which can be charged -if- you can find a charging point which is not being hogged by someone washing their trousers !

Edited by magnetman
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1 hour ago, magnetman said:

The charging stations would have to be bullet proof to avoid abuse though would they not. I don't think charging stations is going to happen. Too complicated. 

 

Battery swaps could be carried out "on the hoof" so to speak. It would become an industry like delivering diesel by boat is currently. Return to a secure base with charging infrastructure maybe even a canalside solar farm...

Obviously the systems would need to be designed to allow reasonably comfortable battery changing without needing steel toe caps. 

 

I can't help noticing rapid advances in the weight and size ie power density of batteries. 

Yes they are still heavy but boats need so little power to propel them and batteries are getting lighter by the hour apparently

ETA they are even talking about 1kwh per killergran.

 

A narrow boat must be about 2kw on an efficient electric drive system so 2kg of batteries per hour doesn't seem to be too terrible.

 

Current batteries seem to be about ten times heavier but time has a funny habit of sorting these things out. 

 

Imagine if you could buy a 13kg bottle of batteries and get a day's boating out of it then exchange for a new one. That might catch on. With your own battery as well which can be charged -if- you can find a charging point which is not being hogged by someone washing their trousers !

I can't see the boating market following anything other than the car market on batteries. EV usage will dictate battery direction for years if not forever.

For EV use, battery technology will be the key advantage each car company will have so I can't see replaceable batteries anytime soon. Tesla have very complex battery technology and are probably 5 years ahead of the competition so they will not give that up easily. Also remember today you need a fork lift to move the battery pack on a Tesla ...10 times the size of the pack on my boat. Yes, they will get smaller but significant improvements will be 10 years away.

Its nice to think of chargers around the network or replaceable battery packs but there is no commercial basis for doing this so it ain't goin to happen. Solar, Li's and big alternators will work for canal boats for the next 20 years.

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We are fast moving to a society that is increasingly divided.

 

Those that can afford electric propulsion of their cars and access to all the associated gubbins to charge them.

 

And those who cannot.

 

To keep on topic substitute boat for car.

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8 hours ago, The Happy Nomad said:

We are fast moving to a society that is increasingly divided.

 

Those that can afford electric propulsion of their cars and access to all the associated gubbins to charge them.

 

And those who cannot.

 

To keep on topic substitute boat for car.

We are not moving to it, we are there now.....but that is for electric propulsion, not replacing LAs.

Used Li's from EVs are cheap enough for the masses and will get cheaper as more EVs crash and are written off.

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9 hours ago, The Happy Nomad said:

We are fast moving to a society that is increasingly divided.

 

Those that can afford electric propulsion of their cars and access to all the associated gubbins to charge them.

 

And those who cannot.

 

To keep on topic substitute boat for car.

Its not expensive now, most of the costs for my conversion were covered by the sale of the diesel engine and gearbox, ok I am an engineer so I did it myself, but as time goes on I could easily put together kits from forklift trucks if I felt like some extra money in my life, which I dont as I value my time to much

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17 minutes ago, peterboat said:

Its not expensive now, most of the costs for my conversion were covered by the sale of the diesel engine and gearbox, ok I am an engineer so I did it myself, but as time goes on I could easily put together kits from forklift trucks if I felt like some extra money in my life, which I dont as I value my time to much

Thats the issue though. Most people would not have the skills to do it themselves and would need to pay someone else to do it. And lets face it reliable trust worthy  engineers who work on boats do not exactly come cheap!

 

Im all for the the future being 'electric', both for vehicles and boats but not if it prices the less well off out of the basic need for independent transport and their hobby or indeed their residence in the case of boats. Thankfully it should be a transitional process and existing propulsion methods will run untill they die out naturally.

 

Unfortunately though in the current climate (pun intended) punitive emmissions charges are seen as a way of driving the changes forwards quicker than perhaps some people will be able to cope with.

 

 

 

 

 

Edited by The Happy Nomad
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12 hours ago, The Happy Nomad said:

We are fast moving to a society that is increasingly divided.

 

Those that can afford electric propulsion of their cars and access to all the associated gubbins to charge them.

 

And those who cannot.

 

To keep on topic substitute boat for car.

Not really. When I was a child most people didn’t have a car. Now they do, but it is a very recent thing in the great scheme of things. Bottom line is that with the population growth and increasing wealth, long term we cannot have private fossil-fuelled cars for everyone. Moving away from that to electric is more expensive. Traditionally when there is a limited resource, it is managed by pricing. So poor people won’t be able to afford it. It was always thus, even if it offends any socialist tendencies you might have. The socialists expect “they” will pay for poor people to have stuff they can’t afford, whilst not specifying where the money “they” will give them, comes from.

 

Of course if our public transport wasn’t worse than most 3rd world countries, it would be better.

Edited by nicknorman
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15 minutes ago, nicknorman said:

Not really. When I was a child most people didn’t have a car. Now they do, but it is a very recent thing in the great scheme of things. Bottom line is that with the population growth and increasing wealth, long term we cannot have private fossil-fuelled cars for everyone. Moving away from that to electric is more expensive. Traditionally when there is a limited resource, it is managed by pricing. So poor people won’t be able to afford it. It was always thus, even if it offends any socialist tendencies you might have. The socialists expect “they” will pay for poor people to have stuff they can’t afford, whilst not specifying where the money “they” will give them, comes from.

 

Of course if our public transport wasn’t worse than most 3rd world countries, it would be better.

Regression to what was in place 50 years ago is hardly the indicator of a progressive modern society.

 

Edit - to be clear I wasnt advocating that fossil fueld cars be available to everyone, just that replacement fuelled vehicles be affordable to those that can afford them now. 

Edited by The Happy Nomad
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From the pollution/CO2 point of view there's little point forcing all ~30k UK canal boats to switch (expensively!) from diesel to electric, they contribute maybe 0.01% of the CO2 that ~30M cars do, the money would be far better spent pushing up EV use and efficiency. But logic doesn't come into it, I'm sure that they'll get caught in in the eliminate-diesel hysteria.

 

Quiet vibration-free boats with no exhaust fumes though, that's a very good reason to do it. Yes charging points would be needed, but in reality this is a tiny problem compared to the car one which *will* be solved. Could even go through Dudley tunnel if the boat would fit...

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17 hours ago, The Happy Nomad said:

We are fast moving to a society that is increasingly divided.

 

Those that can afford electric propulsion of their cars and access to all the associated gubbins to charge them.

 

And those who cannot.

 

To keep on topic substitute boat for car.

The cost benefit equation is still marginal for many. Almost 7 years ago I bought a car that would hold the dog's cage and seat 5. It cost me about £7k. Since then I've put on 100,000 miles and spent another £21k (servicing, MOT, parking; everything). I have 600+ mile range which means I can visit any member of my family and return on the single tank of fuel. Cost per mile = 28p.

 

If I replace with a BEV how much do I have to pay? And, for the time being, I have to get into the habit of recharging near my destination. It doesn't yet make sense for me to make that change. Maybe in a couple of years there will be a better choice of second hand BEVs at more affordable prices and wider uptake should mean better charging availability.

 

I've no doubt the cost of using a diesel car will increase to "encourage" a change to clean propulsion.

 

20 hours ago, magnetman said:

A narrow boat must be about 2kw on an efficient electric drive system so 2kg of batteries per hour doesn't seem to be too terrible.

 

Current batteries seem to be about ten times heavier but time has a funny habit of sorting these things out. 

 

Imagine if you could buy a 13kg bottle of batteries and get a day's boating out of it then exchange for a new one. That might catch on. With your own battery as well which can be charged -if- you can find a charging point which is not being hogged by someone washing their trousers !

You can look at that another way: the 16A mains supply found on most marinas can supply 3.5kWh or 28kWh on an 8 hour charge. @peterboat will tell us how far he can get on 28kWh. Fast charger arrays could be sited around the network at busy points (Hilmorton, Braunston etc, etc.) providing maybe 350kWh (how many days cruising in an hour?) if your battery is big enough.

 

 

Edited by George and Dragon
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37 minutes ago, George and Dragon said:

The cost benefit equation is still marginal for many. Almost 7 years ago I bought a car that would hold the dog's cage and seat 5. It cost me about £7k. Since then I've put on 100,000 miles and spent another £21k (servicing, MOT, parking; everything). I have 600+ mile range which means I can visit any member of my family and return on the single tank of fuel. Cost per mile = 28p.

 

If I replace with a BEV how much do I have to pay? And, for the time being, I have to get into the habit of recharging near my destination. It doesn't yet make sense for me to make that change. Maybe in a couple of years there will be a better choice of second hand BEVs at more affordable prices and wider uptake should mean better charging availability.

 

I've no doubt the cost of using a diesel car will increase to 'encourage" a change to clean propulsion.

 

You can look at that another way: the 16A mains supply found on most marinas can supply 3.5kWh or 28kWh on an 8 hour charge. @peterboat will tell us how far he can get on 28kWh. Fast charger arrays could be sited around the network at busy points (Hilmorton, Braunston etc, etc.) providing maybe 350kWh (how many days cruising in an hour?) if your battery is big enough.

 

 

Mine is a big heavy widebeam it uses 3.3 kw cruising or it did on its 60 volt battery bank, it might have changed now I am on 72 volts. I have 36KWHs of battery bank but I also have 4.6KW of solar on the roof, so working things out can be very difficult! If it was a NB I suspect 2KW would push the boat along nicely maybe less? But you would have less solar to recharge and that is key to electric cruising currently. I do noy see the point of making electric by diesel genny except in emergency solar is best for me

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