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Cheap LiFePO4 BMS?


jetzi

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19 minutes ago, jetzi said:

 

Sounds great. Any desire to connect the BMS to the internet to allow you to set the combi to fast charge if you are not on the boat? Can imagine that would be useful so that the battery is full by the time you arrive ready for your cruise. Perhaps would be nice to be able to monitor the SoC remotely as well.

No, I didn’t make any provision for internet connection. I know it’s the “in thing” but I’m an old Luddite! We do have a GSM remote device which I can interrogate by text to determine that battery voltage (and to put the heating on, which was its main raison d’etre) but apart from anything else I have no more spare IO on the microprocessor. Since we live 425 miles away, any cruise normally starts the day after the long drive down!

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On 14/10/2021 at 11:39, Tony1 said:

ETA- I think I remember you saying that you are a CCer. Is it much of a hassle to transport petrol back to the boat? 

Would it be a pain without a car? 

I did try out a cheap genny to reduce the engine hours spent on charging, but after a couple of trips (on foot and bike) to nearby petrol station forecourts with my jerrycan, I went off the idea. 

But I can see that with a nice quiet genny, it makes sense to use that, and save loads of running hours on your expensive diesel engine. 

 

 

 

Not a CCer. I have a club mooring about 10 minutes drive from home, so spend a few nights aboard each week. No shore power, hence the genny - which lives in one of those Keter plastic shed like things, on the shore, as does the petrol. Not sure what I would do if I was a CCer - gas locker type thing for genny and petrol, and a regular search for a petrol station near a mooring - perhaps a walk with a trolley, rather than a bike ride? Probably end up running the engine :) 

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23 hours ago, Tony1 said:

 

Hi Richard, apologies for pestering you with questions but I've just got my new victron battery protect, planning to install it tomorrow, and just noticed something that Jetzi also mentioned, which is a statement that the BP should not be connected to devices with capacitors on their inputs, e.g. an inverter. 

 

Aha! that'll be it :)

 

23 hours ago, Tony1 said:

They suggest that in these cases you use the BPs relay function to switch off the inverter-....

 

Sounds good to me.

 

23 hours ago, Tony1 said:

but what about the 12v loads? Its hardly a complete solution. 

 

Not sure what you mean by this... the BP cuts off the 12V domestics in a low voltage situation.

 

 

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12 minutes ago, nicknorman said:

No, I didn’t make any provision for internet connection. I know it’s the “in thing” but I’m an old Luddite! We do have a GSM remote device which I can interrogate by text to determine that battery voltage (and to put the heating on, which was its main raison d’etre) but apart from anything else I have no more spare IO on the microprocessor. Since we live 425 miles away, any cruise normally starts the day after the long drive down!

 

If you are driving 425 miles to cruise, then that makes complete sense. I have Victron kit so I set up a Raspberry Pi running Venus software so that I can at least keep an eye on things, but generally speaking I'm also not really a big fan of connecting everything to the internet. Feels like asking for trouble.

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17 minutes ago, Tony1 said:

 

But if you're going out cruising, there's no point wasting charge beforehand getting the batteries up to 80% or 100%? 

Won't the cruising get them up to full charge?

 

I never have shore power these days (although I remember it being a lot cheaper than diesel-generated electricity), so maybe my approach is different as a CCer.

But if I know I'm going cruising the next day, I wont worry if the batteries go a bit low the day before, because I know they'll be getting a good long charge once I set off. 

 

I would never dare charge to 100% remotely in order to synchronise, if I was not there in person. Is it worth it?  

That said, I'm not an electrical wizard, so I would have an innate hesitance about pushing the batteries to extremes when I'm not around.  

 


The cruising would get them up to full charge, but I think the general consensus is that charging batteries from the mains is cheaper than from an inefficient Diesel engine. Plus of course charging from diesel is definitely all carbon footprint, whereas charging from the mains has elements of wind and nuclear power generation. And depends on the distance to be cruised, of course! One destination for us is Kingsbury water park (bottom of Curdworth) which is about an hour away, and makes for a very pleasant and tranquil alternative to the Marina.

 

The algorithm for terminating the charge at 100% is EITHER voltage above x and current below y, OR any one cell voltage above 3.65v. So what could possibly go wrongwrongwrongwrong?

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6 minutes ago, nicknorman said:


The cruising would get them up to full charge, but I think the general consensus is that charging batteries from the mains is cheaper than from an inefficient Diesel engine.

 

And depends on the distance to be cruised, of course! One destination for us is Kingsbury water park (bottom of Curdworth) which is about an hour away, and makes for a very pleasant and tranquil alternative to the Marina.

 

 

What I'm saying is that you're going cruising anyway, right? So the diesel is going to be used up anyway, for that purpose. 

So why not get the extra (and free) benefit of doing the battery charging whilst you're on the move?

After all, your system is capable of delivering a very large charge even in an hour's cruise. 

 

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Oh and the other thing I forgot to mention is that we have “shore power” available  on the boat in the form of the Travelpower. So engine running with switch to Fast gives up to 175A from the alternator(reduces as alternator heats up, maybe 120A continuous). Now switch on the Travelpower and another 90A (from the Combi) comes into play, so we can charge at over 200A if we want to. Or even if the Travelpower is on, we can switch to Slow which means we charge at about 85A and the Travelpower just supplies any AC loads like the tumble drier.

5 minutes ago, Tony1 said:

 

What I'm saying is that you're going cruising anyway, right? So the diesel is going to be used up anyway, for that purpose. 

So why not get the extra (and free) benefit of doing the battery charging whilst you're on the move?

After all, your system is capable of delivering a very large charge even in an hour's cruise. 


No that is a misconception. The alternator generating charge puts a mechanical load on the engine (you don’t get owt for nowt) so the fuel consumption is increased. It’s an interesting question what the marginal efficiency of that is, I don’t have that data, but I doubt it is going to be more than 25%.

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45 minutes ago, Richard10002 said:

 

1.   Aha! that'll be it :)

 

2.  Sounds good to me.

 

 

On that first point, I would want to check that the BP will work via two 'routes' simultaneously, i.e. direct disconnection of 12v loads, plus remote switch off of the inverter.

If I read the instructions correctly (which is admittedly far from certain), my BP will not perform any of its preset disconnects, if a remote switch is plugged into it, so I'm a bit wary of assuming these things will do all the things I might initially expect. 

Don't get me wrong- I'd be fairly confident the BP will work as you've planned it, but I would be inclined to test it out. 

 

This remote switch off function of the BP was no use to me. My inverter has a socket that looks like an RJ45 type, and that means it might be switch-offable by a remote, but I cant be sure, and anyway I dont know which of the wires in the RJ45 thing would connect to which wires on the BP unit, so I didnt even go there. 

So in my case, the BP was no use, and I ended up using it as a high-voltage disconnect instead- and to be fair, when controlled by a BMV712, it seems to do that job very well. 

 

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Sorry about the length of this post, didn't realise it would end up so long! Thought I'd provide an update, and my plans going forward after living with these for 3 years and just going into our 4th winter.

 

Nothing wrong with our setup, it's just having lithium batteries has transformed our usage patterns, and we're beginning to notice the limitations of the original install.

 

I've just completed a full charge/discharge cycle until low cell voltage cut off to check capacity. Batteries are still showing exactly the same capacity as when installed 3 years ago which is great news and such a welcome change from lead acid, particularly for full time family liveaboard! BMV reads between 12-13% when the BMS low cell voltage disconnects, same as it always has on these tests. After 3 years I've just about adjusted my thinking on charging and managing batteries. We now tend to run them between 85% and 20%, with only an occasional 100% charge to sync the BMV. 

 

I'm now beginning to wish I'd installed more capacity though, so have just bought four new 200ah cells from Facebook marketplace for £287.50 which I thought was a good price. He still has some available if anyone is looking for bare cells. https://www.facebook.com/marketplace/item/342945427217664/

 

I know they're a different make and capacity from what I have, but from reading around that shouldn't cause any problems. My plan is just to add an extra cell onto each existing parallel set to make a 3p4s battery instead of the existing 2p4s. They might take a few weeks to install though, as need to rebuild cupboard to fit the extra cells in, and new baby taking up lots of my free time!

 

I'm also looking to increase charging rate. With our increased usage, we're now having to charge daily (until I install the extra cells), but would like to reduce charging time (and therefore engine running!) as much as practical. 

 

Initially we were charging at around 100A between the 2 alternators, but soon discovered this burnt out the domestic alternator! Since tweaking the settings on our alternator controller, we've settled on around 70A as being a good compromise, and not had any further failures since (around 2.5 years). That's with twin 70A A127 alternators, with the domestic one controlled from advanced controller, and standard engine alternator just paralleled until voltage rises to 14v. Engine alternator runs on a smaller engine pulley though. 

 

Plan is to change these to a pair of 90A Ford Mondeo alternators from ebay for around £25ea. I think this is probably the max I can expect to reliably run from single v belts, and changing to poly v jis ust going to cost too much. One is already installed as domestic alternator, and controlled from same controller as previously with same settings. This has already seen the charge increase to a consistent 90A+ and was a direct swap after changing the alternator pulley over. Just need to install the second one as the engine alternator now. Hoping when both are installed, to see reliable charging around the 120-140A which would be a very useful increase if it is!

 

Will let you know how the upgrades go if anyone's interested. The rest of the system just seems to work with no intervention or maintenance, and has performed faultlessly for the past 3 years (other than initial alternator problems).

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8 minutes ago, Tom and Bex said:

Sorry about the length of this post, didn't realise it would end up so long! Thought I'd provide an update, and my plans going forward after living with these for 3 years and just going into our 4th winter.

 

Nothing wrong with our setup, it's just having lithium batteries has transformed our usage patterns, and we're beginning to notice the limitations of the original install.

 

I've just completed a full charge/discharge cycle until low cell voltage cut off to check capacity. Batteries are still showing exactly the same capacity as when installed 3 years ago which is great news and such a welcome change from lead acid, particularly for full time family liveaboard! BMV reads between 12-13% when the BMS low cell voltage disconnects, same as it always has on these tests. After 3 years I've just about adjusted my thinking on charging and managing batteries. We now tend to run them between 85% and 20%, with only an occasional 100% charge to sync the BMV. 

 

I'm now beginning to wish I'd installed more capacity though, so have just bought four new 200ah cells from Facebook marketplace for £287.50 which I thought was a good price. He still has some available if anyone is looking for bare cells. https://www.facebook.com/marketplace/item/342945427217664/

 

I know they're a different make and capacity from what I have, but from reading around that shouldn't cause any problems. My plan is just to add an extra cell onto each existing parallel set to make a 3p4s battery instead of the existing 2p4s. They might take a few weeks to install though, as need to rebuild cupboard to fit the extra cells in, and new baby taking up lots of my free time!

 

I'm also looking to increase charging rate. With our increased usage, we're now having to charge daily (until I install the extra cells), but would like to reduce charging time (and therefore engine running!) as much as practical. 

 

Initially we were charging at around 100A between the 2 alternators, but soon discovered this burnt out the domestic alternator! Since tweaking the settings on our alternator controller, we've settled on around 70A as being a good compromise, and not had any further failures since (around 2.5 years). That's with twin 70A A127 alternators, with the domestic one controlled from advanced controller, and standard engine alternator just paralleled until voltage rises to 14v. Engine alternator runs on a smaller engine pulley though. 

 

Plan is to change these to a pair of 90A Ford Mondeo alternators from ebay for around £25ea. I think this is probably the max I can expect to reliably run from single v belts, and changing to poly v jis ust going to cost too much. One is already installed as domestic alternator, and controlled from same controller as previously with same settings. This has already seen the charge increase to a consistent 90A+ and was a direct swap after changing the alternator pulley over. Just need to install the second one as the engine alternator now. Hoping when both are installed, to see reliable charging around the 120-140A which would be a very useful increase if it is!

 

Will let you know how the upgrades go if anyone's interested. The rest of the system just seems to work with no intervention or maintenance, and has performed faultlessly for the past 3 years (other than initial alternator problems).

 

 

Thanks Tom and Bex- so you can get four 200Ah cells to make a full battery, for under £300? 

I'm seriously tempted, because on cruising days (and good solar days) I could store up hundreds of Ah worth of charge, for use on the following days.

But my worry is whether I could use them seamlessly alongside my existing three Valence batteries.... 

 

 

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3 minutes ago, Tony1 said:

Thanks Tom and Bex- so you can get four 200Ah cells to make a full battery, for under £300? 

You can get the bare cells for that, but would need a bms to go with them. That's already in place with the existing cells in our setup. Minium would be ability to monitor individual cell voltages, and ideally control systems (or loud alarm) based on those.

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1 minute ago, Tom and Bex said:

You can get the bare cells for that, but would need a bms to go with them. That's already in place with the existing cells in our setup. Minium would be ability to monitor individual cell voltages, and ideally control systems (or loud alarm) based on those.

 

Even adding the price of s BMS and a battery case, its still a fantastic price.

Nowadays I'm ok with the idea of building the battery myself, and adding an off the shelf BMS unit- there are some very good and configurable ones available these days. 

 

Thats a 200Ah lithium battery built for about £400. Wow 

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20 minutes ago, Tony1 said:

 

Even adding the price of s BMS and a battery case, its still a fantastic price.

Nowadays I'm ok with the idea of building the battery myself, and adding an off the shelf BMS unit- there are some very good and configurable ones available these days. 

 

Thats a 200Ah lithium battery built for about £400. Wow 

That's the difference a few years make. 3 years ago I paid £600 for 320ah of used cells! These new ones are still in the original boxes as shipped from China. Calb so not a cheap unheard of brand either. 

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2 hours ago, Tony1 said:

What I'm saying is that you're going cruising anyway, right? So the diesel is going to be used up anyway, for that purpose. 

So why not get the extra (and free) benefit of doing the battery charging whilst you're on the move?

After all, your system is capable of delivering a very large charge even in an hour's cruise. 

The energy has to come from somewhere, the alternator will increase fuel consumption if it is charging your battery. It's actually quite easy to demonstrate this if you are able to turn your alternators on and off, my engine (granted it's a small Beta 38) audibly labours if I turn on the alternators while it's running at low revs. I hear a similar argument when people treat electricity as free while the motor is running. Any amps that are going to domestic loads are amps that aren't going into your batteries. The situation can be a bit different with LAs and their low charge rate but generally speaking your LiFePOs can absorb as much as your alternators can provide.

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11 hours ago, Tom and Bex said:

That's the difference a few years make. 3 years ago I paid £600 for 320ah of used cells! These new ones are still in the original boxes as shipped from China. Calb so not a cheap unheard of brand either. 

That’s a very good price! I also have 200Ah CALB cells but they were about £600 for 200Ah (£1800 for 600Ah) just a year ago.

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12 hours ago, Tony1 said:

Even adding the price of s BMS and a battery case, its still a fantastic price.

Nowadays I'm ok with the idea of building the battery myself, and adding an off the shelf BMS unit- there are some very good and configurable ones available these days. 

 

What BMS do you have in mind? This whole thread is pretty much about how an off-the-shelf BMS unit is not really available! But admittedly I haven't looked for a long time.

 

I think it isn't helped by the fact that BMS can refer to a very wide range of things - but as Tom and Bex said -

12 hours ago, Tom and Bex said:

Minium would be ability to monitor individual cell voltages, and ideally control systems (or loud alarm) based on those.

- really the only thing that's essential is a way to disconnect the battery on per-cell under/over voltage event (even if that way is just a loud alarm that prompts you to flip the battery disconnect).

 

The main problem I ran into is that the relays in these devices can generally only handle low currents.

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12 hours ago, Tony1 said:

Nowadays I'm ok with the idea of building the battery myself, and adding an off the shelf BMS unit- there are some very good and configurable ones available these days. 

 

I'd second jetzi's question. Which BMSs do you have in mind, because I can't find any that have all the basic functions needed. 

 

The basic essential functions in my opinion are:

 

Separate charge disconnect on any individual cell voltage rising above a value the user can set

Separate load disconnect on any individual cell voltage falling below a value the user can set

Pre-disconnect advance warning (e.g. audio alarm) at user settable values

Charge disconnect at low temp (e.g. 0 degrees C)

High current capacity (say 150A) so use of relays is not required

 

Anyone building such a BMS will surely sell millions! 

 

 

 

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5 minutes ago, jetzi said:

 

What BMS do you have in mind? This whole thread is pretty much about how an off-the-shelf BMS unit is not really available! But admittedly I haven't looked for a long time.

 

I think it isn't helped by the fact that BMS can refer to a very wide range of things - but as Tom and Bex said -

- really the only thing that's essential is a way to disconnect the battery on per-cell under/over voltage event (even if that way is just a loud alarm that prompts you to flip the battery disconnect).

 

The main problem I ran into is that the relays in these devices can generally only handle low currents.

 

As much as I'd love to add more capacity cheaply, my three current units are I think valence U27-12XP (rated at 138Ah), and the new bargain cells are 200Ah.

I dont think you can just add a new 200Ah battery into that existing bank can you?  For one thing, two different types of cell will probably charge at different rates, and the valences might reach 100% SoC long before the 200Ah unit does, etc. It just seems fraught with issues. 

I did see a used Valence recently identical to mine, but it was £500 and collection in person in North London, which effectively adds £100 transport cost to the price. 

 

If I do find a compatible battery that I can build and add in, ideally I'd like one of the high-end BMS kits, this is one of the suppliers:

https://www.batrium.com/collections/kits/products/watchmoncore

 

The essential protection is there already with my disconnect systems, but it would nice to have some balancing functions as well. 

 

This one is 4 years old but it seems to have a good set of features:

 

 

 

 

 

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8 minutes ago, MtB said:

 

I'd second jetzi's question. Which BMSs do you have in mind, because I can't find any that have all the basic functions needed. 

 

The basic essential functions in my opinion are:

 

Separate charge disconnect on any individual cell voltage rising above a value the user can set

Separate load disconnect on any individual cell voltage falling below a value the user can set

Pre-disconnect advance warning (e.g. audio alarm) at user settable values

Charge disconnect at low temp (e.g. 0 degrees C)

High current capacity (say 150A) so use of relays is not required

 

Anyone building such a BMS will surely sell millions! 

 

 

 

REC make one but the price is eye watering to say the least, their latest one is active rather than passive. I fitted one for a mate the other month once the batteries were properly top balanced it worked great! That great it wasn't needed, which is why I carefully top balanced all my batteries before building the banks 

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4 minutes ago, MtB said:

 

I'd second jetzi's question. Which BMSs do you have in mind, because I can't find any that have all the basic functions needed. 

 

The basic essential functions in my opinion are:

 

Separate charge disconnect on any individual cell voltage rising above a value the user can set

Separate load disconnect on any individual cell voltage falling below a value the user can set

Pre-disconnect advance warning (e.g. audio alarm) at user settable values

Charge disconnect at low temp (e.g. 0 degrees C)

High current capacity (say 150A) so use of relays is not required

 

Anyone building such a BMS will surely sell millions! 

 

 

 

 

I hear Batrium make some very good BMS kits, but I dont know if they have all those features- very probably not. 

 

I'm not actively researching them, since I'll struggle to find a battery that I can add to my existing bank seamlessly- perhaps it more of an aspiration.  

 

But if I were to find a compatible battery (or set of cells), and then I got seriously into BMS shopping, I would probably accept some compromises on that full set of features you've listed, if it meant I could save significant money and not run significant risks whilst doing so. 

 

The protection/disconnect features I already have- albeit only an overall level for the whole battery bank, which is why I try to be more conservative, and allow for individual cell variations but still give a decent level of protection. 

I've accepted the risk of basing the disconnects on an overall voltage level for the whole bank, rather than at cell level, so I'd probably be ok with continuing that approach with any new batteries, as long as the new batteries were very similar to the ones I have (which is not likely to be the case unfortunately).

 

If I were starting again from scratch though, your list would be a great starting point. 

  

 

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1 minute ago, Tony1 said:

 

I hear Batrium make some very good BMS kits, but I dont know if they have all those features- very probably not. 

 

I'm not actively researching them, since I'll struggle to find a battery that I can add to my existing bank seamlessly- perhaps it more of an aspiration.  

 

But if I were to find a compatible battery (or set of cells), and then I got seriously into BMS shopping, I would probably accept some compromises on that full set of features you've listed, if it meant I could save significant money and not run significant risks whilst doing so. 

 

The protection/disconnect features I already have- albeit only an overall level for the whole battery bank, which is why I try to be more conservative, and allow for individual cell variations but still give a decent level of protection. 

I've accepted the risk of basing the disconnects on an overall voltage level for the whole bank, rather than at cell level, so I'd probably be ok with continuing that approach with any new batteries, as long as the new batteries were very similar to the ones I have (which is not likely to be the case unfortunately).

 

If I were starting again from scratch though, your list would be a great starting point. 

  

 

James has some Valance batteries for sale Tony nearly new he says 

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Just now, peterboat said:

James has some Valance batteries for sale Tony nearly new he says 

 

 

Cheers Peter, thats good news. My problem is how to get hold of one, now that I've given back the car. 

I guess I could get an off-peak day return train to his top secret location, and the battery would fit into a haversack- can you transport them in the vertical position? 

I'll have a look at the tickets and prices, and if it looks worthwhile I'll give you a shout.  I lost his number when I dropped my phone in the marina last November 

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16 minutes ago, Tony1 said:

two different types of cell will probably charge at different rates, and the valences might reach 100% SoC long before the 200Ah unit does, etc. It just seems fraught with issues. 

This is definitely the case, in fact two of the exact same type of cells reach 100% at different rates. That's why per-cell monitoring is essential, you can't rely on the overall battery voltage.

 

19 minutes ago, Tony1 said:

The essential protection is there already with my disconnect systems, but it would nice to have some balancing functions as well. 

 

I really feel (and think the general consensus among posters here is) that automatic balancing is very non-essential to the point of being of of no real use. The main reason for balancing is to get more capacity out of your bank, and also it makes the setup a little safer because if the cells are well-balanced the whole-battery-voltage disconnect is less likely to exceed the range of any individual cell (which also then allows you to be less conservative with your charge range). But my experience is that the cells don't really get out of balance anyway, I think most of us are reporting the same. It's just not so much of a problem in our relatively low-current environments with our conservative charging ranges.

 

29 minutes ago, MtB said:

I'd second jetzi's question. Which BMSs do you have in mind, because I can't find any that have all the basic functions needed. 

 

The basic essential functions in my opinion are:

 

Separate charge disconnect on any individual cell voltage rising above a value the user can set

Separate load disconnect on any individual cell voltage falling below a value the user can set

Pre-disconnect advance warning (e.g. audio alarm) at user settable values

Charge disconnect at low temp (e.g. 0 degrees C)

High current capacity (say 150A) so use of relays is not required

 

Anyone building such a BMS will surely sell millions!

 

That's a good list and what I'm aiming for - plus I want to add a load dump and an automatic battery heater for when you try to charge below 0 degrees (I have these things at the moment but they're manual). But if we're talking about a bare minimum, I think the only really essential thing is a per-cell alarm (preferably disconnect). And as Tony is finding it's possible (albeit risky) to only use the whole-battery disconnect, as long as your cells are balanced and you aren't aggressive with the high/low SoCs.

 

There's a whole other topic though which is on charge regulation (especially on your alternators) - currently I'm relying on my LA dump battery to pick up the slack from an emergency charge disconnect.

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26 minutes ago, Tony1 said:

 

 

Cheers Peter, thats good news. My problem is how to get hold of one, now that I've given back the car. 

I guess I could get an off-peak day return train to his top secret location, and the battery would fit into a haversack- can you transport them in the vertical position? 

I'll have a look at the tickets and prices, and if it looks worthwhile I'll give you a shout.  I lost his number when I dropped my phone in the marina last November 

Make it quick as his top secret location might be changing 

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9 minutes ago, jetzi said:

But if we're talking about a bare minimum, I think the only really essential thing is a per-cell alarm (preferably disconnect).

 

I disagree. 

 

1) I leave my fridge turned on when I'm not on the boat. This alone makes a "low cell" disconnect mandatory. Agreed the alarm perhaps falls into the 'nice to have' category but I think without the advance warning alarm, one only has to be left sitting in the dark unexpectedly once or twice, to begin to see it as essential.

 

2) Separate channels for load disconnect and charge disconnect are essential too. If you get say, a high cell disconnect you NEED the load circuit to stay connected or how will you discharge the battery to a safe level? Similarly with low voltage disconnect. You NEED the charging devices to remain connected to correct the low SoC.

 

 

16 minutes ago, jetzi said:

And as Tony is finding it's possible (albeit risky) to only use the whole-battery disconnect, as long as your cells are balanced and you aren't aggressive with the high/low SoCs.

 

That's a pretty big 'as long as'. To rely on whole battery voltages one also needs the cells to be closely matched in capacity. If one top-balances, then the cells need to be close to each other in capacity or when fully discharged, one cell will get low first. It strikes me that a lot of users focus unnecessarily closely on balancing, possibly because it's an easy concept to grasp compared to some of the other more important things needed to be accounted for in designing a lithium battery installation.

 

 

 

 

 

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