Simple LifePo swap sense check

[geem]

Oh, are they cheap - I hadn’t noticed!

See they’ve got a pretty conservative continuous discharge rate - still more than enough for me - presumably that is their choice, to prioritise longevity over absolute performance. But I guess I still need to size cable and fuse for the max 400A rate?

Fuse the batteries individually for their rating. NH00 fuses are good value. If you are using an inverter, a breaker is a good choice for that instead of a fuse. Fuse that for the rating of the inverter. For example, my 3000w inverter can deal with a surge of 9000w. Its a 24v inverter. I can pull about 115A at 3000w. I installed a 150A Blue Sea breaker. It's only tripped once when I accidently loaded the inverter to 3750w. It took 20mins to trip. The inverter also has its own inbuilt trip. That didn't trip.
I have my 105Ah battery fused at 160A. The 280A battery is fused at 225A. The BMS on both batteries are rated to 200A. The only way I can impose a large load is through the inverter. With this being limited to 150A by the breaker, the main fuses are safe from a premature pop.
Since my batteries are parallel wired, I have to consider that I may run on one battery if I had a BMS failure on the other.
The smaller battery needs to be able to deal with 150A. Although in this situation, I might be a little more careful of my inverter loads

 

[Pete7]

I'm reading the voltage at the shunt and manually not allowing it to exceed 14v. I'm awaiting a new solar controller so am doing this manually. I'm using a 'condemned' built in BMS, no external control, no reading of individual cells, 200a battery. If I'm unable to monitor, when we are not to be at home, I simply disconnect the solars until we return. Clunky - and hopefully it works.

It is not clear why MC, who seems to be repeating the ABYC, and the ABYC are demanding hard wiring of the BMS and find Blue Tooth, in isolation, unacceptable. There has never been a mention of discomfort to blue tooth here, on YBW (and we have a number of house banks being described). In looking at batteries for sale I commonly see them being promoted with Blue Tooth - but there is never mention of hard wiring (and lots of reputable batteries come from America).

I can see the merit of having advance warning - and Geem in an earlier thread mentioned how he is going to achieve same.

Part of the recommendation is identical to words of warning here - don't use a 'drop in' battery with internal BMS that does not allow owner manipulation.

Interesting that no-one is charging to 14.2v (which I think is the voltage recommended by NASA for their Lithium Clipper shunt and monitor).

I made mention that I have read that if you want to increase the size of your battery bank, this refers to Lithium, that you should use the same sized battery (and the battery ideally should come from the same batch (which seems an impossibility).

If you have a "condemned BMS" in a 200Ah battery, I would be very tempted to rip the top off, remove the BMS and put a JBD or similar with Bluetooth in place. Cost say £60 and a tube of sealant.

The only possible use I can think of for a LFP battery without a Bluetooth or can bus connections would be a small cheap battery to power a trolling motor for the dinghy. You would charge the life out of it until the BMS cut the charging and then put it aside ready to use again. Bit like a torch battery. We are just going down the trolling motor route for the dinghy, but even so chose a 75Ah LFP with Bluetooth. When its not running the electric trolling motor it can do some useful service by being hooked up to the domestic LFP bank and give us an extra 1kW of LFP storage or so.

No point in charging past 14.2v (3.55v per cell) because you are only stressing the battery and there is only a tiny amount of extra capacity beyond 3.45v per cell. You will see many manufacturers recommending 14.6v. They of course aren't worried about battery life, just performance or capacity. You and I on the other hand want our little darlings to "live forever". Think our BMSs are set to 14v.

"Yes, Sir will need new batteries to increase capacity and we have the ideal solution for you at a very good price" . Back in the real world lots of us have just got on with it and joined all sorts of combinations together. We have joined LFP to lead-acid. Then added a new 100Ah LFP to the existing 2 year old 120Ah LFP. The result? Well a few amps flowed between the batteries for a little while and that was it. Just be aware if you mix sizes then the % SOC display shown by Bluetooth etc won't match. For example, draw 50A from a 100A and a 120A battery wired in parallel will result in readings say 50% and 60%. Is this a problem? not in the slightest also be aware that %SOC is only a rough estimate anyway. Something to glance at occasionally, not base charging regimes on.

 

[PaulRainbow]

If you have a "condemned BMS" in a 200A battery, I would be very tempted to rip the top off, remove the BMS and put a JBD or similar with Bluetooth in place. Cost say £60 and a tube of sealant.

The only possible use I can think of for a LFP battery without a Bluetooth or can bus connections would be a small cheap battery to power a trolling motor for the dinghy. You would charge the life out of it until the BMS cut the charging and then put it aside ready to use again. Bit like a torch battery. We are just going down the trolling motor route for the dinghy, but even so chose a 75Ah LFP with Bluetooth. When its not running the electric trolling motor it can do some useful service by being hooked up to the domestic LFP bank and give us an extra 1kW of LFP storage or so.

No point in charging past 14.2v (3.55v per cell) because you are only stressing the battery and there is only a tiny amount of extra capacity beyond 3.45v per cell. You will see many manufacturers recommending 14.6v. They of course aren't worried about battery life, just performance or capacity. You and I on the other hand want our little darlings to "live forever". Think our BMSs are set to 14v.

"Yes, Sir will need new batteries to increase capacity and we have the ideal solution for you at a very good price" . Back in the real world several of us have just go on with it and joined all sorts of combinations together. We have joined LFP to lead-acid. Then added a new 100Ah LFP to the existing 2 year old 120Ah LFP. The result? Well a few amps flowed between the batteries for a little while and that was it. Just be aware if you mix sizes then the % SOC display shown by Bluetooth etc won't match. For example, draw 50A from a 100A and a 120A battery will result in readings say 50% and 60%. Is this a problem? not in the slightest and be aware that %SOC is only a rough estimate anyway. Something to glance at occasionally, not base charging regimes on.

Lot of useful real World experience in there Pete, rather than some of the garbage on the internet.

 

[stranded]

Cheap is all relative, try pricing up Victron to demonstrate to yourself what a bargain they are

That discharge is specced to the BMS. Yes, Class T fuse and cable for something bigger is what I did.

TBS DCM Class-T Fuse Holder M10 (225-400A)

On mine I then connected the Class T fuse holder to one of these for distribution, with the mega fuse leading to main battery switch. The midis are used for MPPT and Eberspacher which are direct connected, and I put two spare midi fuses in there so I can find them easily

Mega-Midi Fuse Box

Re. all these additional fuses…

I know I need an additional mega fuse by the battery. But from a consumer connection point of view I will simply be swapping batteries - all consumers and the charger/inverter already have appropriate fuses/breakers, presumably (it was done professionally) sized to the cables. Are you saying I need to swap these out for new beefed up fuses, or install additional ones? And if so, how do I size them?

 

[lustyd]

Re. all these additional fuses…

I know I need an additional mega fuse by the battery. But from a consumer connection point of view I will simply be swapping batteries - all consumers and the charger/inverter already have appropriate fuses/breakers, presumably (it was done professionally) sized to the cables. Are you saying I need to swap these out for new beefed up fuses, or install additional ones? And if so, how do I size them?

The Class T is probably new/additional and is for short circuit of the battery which can be bad with Lithium - should be very close to the battery and if you have a recent boat from a big builder you may already have one. They blow differently than "normal" fuses and guarantee disconnection under high amperage circumstances whereas a mega fuse and it's housing might under some circumstances end up allowing the short to continue. This is probably the only important change and even then there's a lot of debate about them, but most agree it's a good idea for scenarios like dropping a spanner into the wiring.

The rest you should already have and is not different with lithium. The mega fuse is just the one for your main cable to protect that cable and might very well not be a mega fuse, there are lots of options. That housing worked out neat for my boat since I have the Eber and MPPT permanently connected on the battery side of the main switch. Midi fuses are probably overkill, but again the box was nice and neat so was handy to put it all in as though I'd planned the install

@PaulRainbow will probably give you better advice on this and which parts to use. I went with the parts I could find easily

 

[Pete7]

Re. all these additional fuses…

I know I need an additional mega fuse by the battery. But from a consumer connection point of view I will simply be swapping batteries - all consumers and the charger/inverter already have appropriate fuses/breakers, presumably (it was done professionally) sized to the cables. Are you saying I need to swap these out for new beefed up fuses, or install additional ones? And if so, how do I size them?

Hmm, interesting question. You will be aware that if you drop a spanner across the terminals of a 12v lead acid battery it will become a very good electric heater in a few seconds glowing red hot. Lead acid batteries have an internal resistance and don't like giving up those amps but they will still turn a spanner cherry red.

LifePo4 (LFP) has a much lower resistance and potentially discharge sufficient current that in the event of a short circuit anywhere fuses like ANL will blow but the spark is sufficient to jump the gap and continue to supply power. Forget the internal BMS that will be a sticky pool of molten metal and plastic. Your wiring sized for the load you intend to power like an inverter will also become rather warm.

Therefore as a fuse of last resort many have fitted Class T fuses. I believe they are contained in silica which even if the wire blows then the arc is extinguished. Unfortunately, Class T fuse holders £40 and fuses £45 each are expensive in the UK. So some of use are using the NH00 type which are similar and cheaper in Europe. About £20 for the holder and £5+ for the fuse from the likes of Bimble Solar.

I caught a 3mm hex key once very briefly when tightening up a battery cable in a fuse box. It was only a glancing short, but I now have a hex key with only one usable end. I decided after this to fit an NH00 160A fuse rated just above the maximum load I will ever need to draw and carry a small box of spares just in case. There is also a 150A Bussman circuit breaker in the inverter circuit. The rest are mega fuses etc to each domestic circuit and the incoming supply.

I will second Lustyd's suggestion to listen to Paul Rainbow, I also fused everything I could find based on load and wire size. Hopefully your system will be okay if installed by the manufacturer. The one I had to change was the main supply and return to the domestic panel because I have increased the amount of electronics and added diesel heating.

 

[lustyd]

I'll add, please don't panic about this. It sounds worse than it is, if you just pop in that one extra fuse you're done and safe.

 

[stranded]

I'll add, please don't panic about this. It sounds worse than it is, if you just pop in that one extra fuse you're done and safe.

Thanks - not panicking about this really, just trying to understand what I have to do so I can make sure I do enough but not more than needed. Since I’ve no intention of adding significantly to the loads, and never in 10 years had any issue with the existing set-up, I think I’ll be good with the additional class t fuse - think I’ll not scrimp on that - cheap insurance in the scheme of things. Panic is when Geem started talking about deltas!

You guys are doing a great job demystifying all this - I am expecting the results to be a real step change in our quality of life while off grid. Being a cautious chap I’m going to get my electrics guy to check my work, but I am keen to do the actual installation work myself, so learning in the process.

 

[Kelpie]

Lots of good info about fuses already.
Class T is certainly viewed as the gold standard but a large number of people don't seem to have heard of it. I would say that the majority of people I've discussed lithium installations with (in real life, not forums) are using ANL, Mega fuse, or MRBF.

I haven't fused each battery individually. My biggest possible load under normal circumstances is about 215A. So I fitted a 225A class T. The cables going to each individual battery can handle 485A.
I did consider a bigger fuse but on balance it seemed safer to go just above the real world usage.

 

[Kelpie]

The only possible use I can think of for a LFP battery without a Bluetooth or can bus connections would be a small cheap battery to power a trolling motor for the dinghy.

Slight thread drift, but we have a 60Ah Sterling battery for exactly this purpose.
Lack of Bluetooth is a major drawback. The best I can do is to keep track of the length of time I've been running. But an actual SOC reading would be much better.

At some point, if I stumble upon a suitable case, I might mount the battery inside among with a cheap battery monitor. Plus some Anderson plugs.

The trolling motor project was fun, and my wife quite liked using it until she got the hang of the two stroke. But the Bison motor was not really up to everyday use in seawater, and started falling apart. The cables are also prone to corrosion, because no matter how hard you try you will drop the ends in a puddle in the bottom of the dinghy. I've been gradually shortening and re-crimping mine.

 

[Neeves]

I may have misled you, many.

My condemned shunt is condemned by the members here on the basis its cheap and from China. I recall, maybe Kelpie, uses something similar. Ours, the shunt, is a 100amp version (100amp battery) and I was advised to throw it out and invest in a bigger one from Victron.

I don't know how to measure its efficiency.

But what I do like, and maybe everyone else has something similar, is that it offers a simply meter that can display if you scroll through, voltage, amps flowing, amps left and hence a rough idea of actual capacity. As the meter measures at the shunt this should be battery voltage. My understanding that Blue Tooth offers this, and more (you can interrogate individual cells), except with Blue Tooth you need to be proactive, take your phone out, scroll to the app and then interrogate the battery. I just press a button as I walk past and can forget need of a phone. It displays in a simply image, battery state, and simultaneously displays voltage, amps (in or out). I like the 'ever on' display - no need for Blue Tooth. I know the battery state

If I were to go up market with an inrrogateable BMS - I would still want the simply display.

Maybe this is what Morgans Cloud demand to have hard wiring means.

So a question is:

Most appear to have Blue Tooth, though GHA has no BMS and Kelpie, if my memory is correct, originally managed without:

Does everyone have a visual display, permanently 'on' as well as Blue Tooth? And is the permenant display measuring at the shunt? Or are people relying on Blue Tooth?

I appreciate that the capacity, as a percentage, is a guesstimate (and may become less accurate with time so needs recalibration) but to me I really don't care if it says 40% but is actually 60% - its good enough and the battery voltage is the crucial data point when nearing 90% and more.

On the potential for a short. I took the danger on board and pondered how to minimise the risks. In the end I took a simple piece of plastic domestic water pipe, slit it to fit over the terminals and cable tied it down - no exposed eye nor battery terminals. The pipe covers from negative to positive pole. I did the same for the shunt and the main negative bus bar. Not pretty but nothing is exposed. It would have been better if I had thought about this at the outset - it might then have been neater - maybe a series of hinged acrylic lids - but in the fullness of time I can change this. Each of the battery poles has a silicone sleeve covering the pole and the eye - belt and braces.

I took on board Paul's instruction that the battery poles should have only one eye connected and introduced a negative bus bar, the positive pole still has 3 eyes and I need to introduce a positive bus bar.

Jonathan

 

[Kelpie]

GHA has no BMS and Kelpie, if my memory is correct, originally managed without:

No, I have never operated a lithium battery without a BMS, and I would never advocate doing so.

 

[Pete7]

So a question is:

Does everyone have a visual display, permanently 'on' as well as Blue Tooth? And is the permanent display measuring at the shunt? Or are people relying on Blue Tooth?

I appreciate that the capacity, as a percentage, is a guesstimate (and may become less accurate with time so needs recalibration) but to me I really don't care if it says 40% but is actually 60% - its good enough and the battery voltage is the crucial data point when nearing 90% and more.

Jonathan

We have a visual display but its a 16 yr old Sterling monitor so may as well use it for something. The SOC is given in Ah but it wanders out of sync after a few days use unless I hit 100%. Then it goes back to being accurate again, for a while. Victron is the popular battery monitor option, but Amazon is full of cheap copies or a half way option might be Renogy.

 

[stranded]

We have a visual display but its a 16 yr old Sterling monitor so may as well use it for something. The SOC is given in Ah but it wanders out of sync after a few days use unless I hit 100%. Then it goes back to being accurate again, for a while. Victron is the popular battery monitor option, but Amazon is full of cheap copies or a half way option might be Renogy.

We have a Mastervolt display that, through the Masterbus network, provides comprehensive information on batteries, charger, inverter, generator before it died, and allows all the important parameters to be changed remotely.

The batteries are measured through a 500A Mastershunt which is reasonably accurate but is about 0.5m from the battery terminals and it calculates soc by what goes into and what comes out of the batteries, so drifts slightly over time. It is fine for giving an indication of how much gas is left in the tank, but I assume that the Victron Smartsense, because it measures voltage at the terminals, is going to be more reliably accurate for the purpose of charging the battery to a precise voltage.

 

[geem]

Lots of good info about fuses already.
Class T is certainly viewed as the gold standard but a large number of people don't seem to have heard of it. I would say that the majority of people I've discussed lithium installations with (in real life, not forums) are using ANL, Mega fuse, or MRBF.

I haven't fused each battery individually. My biggest possible load under normal circumstances is about 215A. So I fitted a 225A class T. The cables going to each individual battery can handle 485A.
I did consider a bigger fuse but on balance it seemed safer to go just above the real world usage.

I think if you are individually

I may have misled you, many.

My condemned shunt is condemned by the members here on the basis its cheap and from China. I recall, maybe Kelpie, uses something similar. Ours, the shunt, is a 100amp version (100amp battery) and I was advised to throw it out and invest in a bigger one from Victron.

I don't know how to measure its efficiency.

But what I do like, and maybe everyone else has something similar, is that it offers a simply meter that can display if you scroll through, voltage, amps flowing, amps left and hence a rough idea of actual capacity. As the meter measures at the shunt this should be battery voltage. My understanding that Blue Tooth offers this, and more (you can interrogate individual cells), except with Blue Tooth you need to be proactive, take your phone out, scroll to the app and then interrogate the battery. I just press a button as I walk past and can forget need of a phone. It displays in a simply image, battery state, and simultaneously displays voltage, amps (in or out). I like the 'ever on' display - no need for Blue Tooth. I know the battery state

If I were to go up market with an inrrogateable BMS - I would still want the simply display.

Maybe this is what Morgans Cloud demand to have hard wiring means.

So a question is:

Most appear to have Blue Tooth, though GHA has no BMS and Kelpie, if my memory is correct, originally managed without:

Does everyone have a visual display, permanently 'on' as well as Blue Tooth? And is the permenant display measuring at the shunt? Or are people relying on Blue Tooth?

I appreciate that the capacity, as a percentage, is a guesstimate (and may become less accurate with time so needs recalibration) but to me I really don't care if it says 40% but is actually 60% - its good enough and the battery voltage is the crucial data point when nearing 90% and more.

On the potential for a short. I took the danger on board and pondered how to minimise the risks. In the end I took a simple piece of plastic domestic water pipe, slit it to fit over the terminals and cable tied it down - no exposed eye nor battery terminals. The pipe covers from negative to positive pole. I did the same for the shunt and the main negative bus bar. Not pretty but nothing is exposed. It would have been better if I had thought about this at the outset - it might then have been neater - maybe a series of hinged acrylic lids - but in the fullness of time I can change this. Each of the battery poles has a silicone sleeve covering the pole and the eye - belt and braces.

I took on board Paul's instruction that the battery poles should have only one eye connected and introduced a negative bus bar, the positive pole still has 3 eyes and I need to introduce a positive bus bar.

Jonathan

The Jk BMS has a visual display as an option. We have one. It's output is of limited use. It shows battery voltage, amps and SOC. The SOC is never very accurate compared to the Victron shunt.
Do you have a fuse on the battery? You really need to fuse the +ve side. Ideally with 7" of the terminal. If its longer, sleeve the cable in some plastic pipe. You can then use a simple power pole of busbar to connect your three cables. NH00 fuses are not expensive. Just as good as Class T but a fraction of the price

 

[Neeves]

I think if you are individually
The Jk BMS has a visual display as an option. We have one. It's output is of limited use. It shows battery voltage, amps and SOC. The SOC is never very accurate compared to the Victron shunt.
Do you have a fuse on the battery? You really need to fuse the +ve side. Ideally with 7" of the terminal. If its longer, sleeve the cable in some plastic pipe. You can then use a simple power pole of busbar to connect your three cables. NH00 fuses are not expensive. Just as good as Class T but a fraction of the price

I'm not unhappy that our SOC is not particularly accurate, knowing its 'about' 60% or 80% is good enough. If its 20% I know that we need to be parsimonious with usage - if its 80% I know we can use as much as we want.

I can display volts at the shunt/battery and SOC simultaneously and if the voltage is at 14v I assume that the SOC will be near 85%, approx. The theoretical max on the internal BMS is 14.8v (which based on these threads seems a bit high) - but we try to keep the voltage below 14.2v, preferably 14.0v, (I'm currently managing this manually - because the solar controller is inoperative (and I'll make it the subject of a different post).

The battery is fused, but a bit more than 7" from the +ve pole, maybe 10" - which I thought was 'close'.

Jonathan

 

[Neeves]

Solar Controller.

Currently our solar controller is inoperative, not sure why.

We have a MPPT controller on order, it should arrive within a week. The order has been a bit delayed....

Because when the controller originally arrived it was not lithium compatible and the instructions specifically said only for Lead batteries. We had bought through Temu and complained. They immediately refunded the cost of the controller, we had paid through PayPal. We queried about return of the unit and they said:

Forget it, dump it, give it to a charity, sell it on eBay.

So we have won a Lead MPPT controller and have another, Lithium compatible, MPPT, controller on order.

I have 2 concerns.

There is a little string of connectors on the base of the Lead controller, 2 for the solar panels, 2 to the battery and 2 for a domestic load. Each pair are 1 +ve and 1 -ve. Each connector will accept a 3mm wire - which seems inadequate for a 100 amp controller. I am fearing that the new Lithium controller will be similar - they look almost identical from the one we have and the picture of the replacement - how do I connect a heavy duty cable, its 10m long, to such a small connector point.

If/when the new controller arrives how can I determine if it is a MPPT or a PWM controller? Comments in past on YBW have said many Chinese controllers are said to be MPPT but turn out to be PWM - how does anyone know.

I'm in the fortunate position I'm willing to test the boundaries of quality - in this case the controllers are cheap and the return policy (if the controller is wrong) seems robust.

Jonathan

One reason I persist with Chinese sourced products, other than cost....

The Chinese appear to be leading the world in alternative battery technology and in EVs. In Australia, I stand to be corrected, all EVs here are from China. There is no cacophony of complaint of EVs. EVs need BMS and an ability to indicate battery state - these various controls from China appear to be acceptable. I appreciate the market for EVs is considerably more attractive than 'our' market - but I find it difficult to accept that there is not any trickle down effect - and MPPT controllers, B2B units, inverters are hardly novel - they have been around for years, decades. If I had to comment on Chinese innovation I might say they are experts at copying any device that offers an income - for example their phones are as good as Google or Apple, they make Lithium cells lauded by people here.....

J

 

[Neeves]

You guys are doing a great job demystifying all this - I am expecting the results to be a real step change in our quality of life while off grid. Being a cautious chap I’m going to get my electrics guy to check my work, but I am keen to do the actual installation work myself, so learning in the process.

I think one of the complaints of today's generation of boat owners is that too many lack any knowledge of the systems currently available to support their yacht. It used to be said they might be cheque book sailors (until we all stopped using cheques - and I don't know the current term). Yachts used to be quite simple - today they are quite complex (and getting more so).

But if you do the work yourself, supported by the knowledge base here, you will have a good idea of what the issues might be if something goes wrong.

Its what PBO is meant to be about.

Jonathan

 

[geem]

[QUOTE="Neeves, post: 8340670, member:

The battery is fused, but a bit more than 7" from the +ve pole, maybe 10" - which I thought was 'close'.

Jonathan
[/QUOTE]
It's worth adding some sleeve material between fuse and +ve battery terminal if it's feasible. ABYC says 7" maximum. They recommend sleeving if its longer than this.
I added a sheet of perspex over the top of my DIY batteries so nothing could drop on to the cell terminals by accident. The perspex stands off the cells about 2 inches so still allows good ventilation. I know you don't have a DIY battery but a similar solution could protect your terminals but still allow you to see them.

 

[geem]

Solar Controller.

Currently our solar controller is inoperative, not sure why.

We have a MPPT controller on order, it should arrive within a week. The order has been a bit delayed....

Because when the controller originally arrived it was not lithium compatible and the instructions specifically said only for Lead batteries. We had bought through Temu and complained. They immediately refunded the cost of the controller, we had paid through PayPal. We queried about return of the unit and they said:

Forget it, dump it, give it to a charity, sell it on eBay.

So we have won a Lead MPPT controller and have another, Lithium compatible, MPPT, controller on order.

I have 2 concerns.

There is a little string of connectors on the base of the Lead controller, 2 for the solar panels, 2 to the battery and 2 for a domestic load. Each pair are 1 +ve and 1 -ve. Each connector will accept a 3mm wire - which seems inadequate for a 100 amp controller. I am fearing that the new Lithium controller will be similar - they look almost identical from the one we have and the picture of the replacement - how do I connect a heavy duty cable, its 10m long, to such a small connector point.

If/when the new controller arrives how can I determine if it is a MPPT or a PWM controller? Comments in past on YBW have said many Chinese controllers are said to be MPPT but turn out to be PWM - how does anyone know.

I'm in the fortunate position I'm willing to test the boundaries of quality - in this case the controllers are cheap and the return policy (if the controller is wrong) seems robust.

Jonathan

One reason I persist with Chinese sourced products, other than cost....

The Chinese appear to be leading the world in alternative battery technology and in EVs. In Australia, I stand to be corrected, all EVs here are from China. There is no cacophony of complaint of EVs. EVs need BMS and an ability to indicate battery state - these various controls from China appear to be acceptable. I appreciate the market for EVs is considerably more attractive than 'our' market - but I find it difficult to accept that there is not any trickle down effect - and MPPT controllers, B2B units, inverters are hardly novel - they have been around for years, decades. If I had to comment on Chinese innovation I might say they are experts at copying any device that offers an income - for example their phones are as good as Google or Apple, they make Lithium cells lauded by people here.....

J

Yes, and the Chinese Jk BMS is probably thr best BMS currently on the market. Your Aussie based German, .Andy from Off grid Garage on Utube tests the hell out of all the BMS and he reckons the Jk is the best. I have two of them.
If you want the best MPPTs, smart shunts, etc. Victron is hard to beat