Lithium Batteries installation

[IanD]

13 minutes ago, dmr said:

The TravelPower is pretty much essential to our boaty lives, its the lovely old black box incarnation, but there is really now only Mr Cox who knows how to fix it and he admits that his spare parts will run out at some stage. I want a PlanB ready in case it dies (or Cox's loose interest) and this would be a dedicated 24/48 volt alternator/inverter/battery to completely replace the TravelPower.

I should really convert the whole boat to 24/48 and run the 12 volt system off a dc-dc dropper but I like the redundancy obtained from totally separate systems.

We did witness a boat fire a couple of years ago and this was down to running a washing machine off a 12 volt system. My own rule of thumb is 100amps max, 150 absolute max, so 24 or 48 is the way to go for washing machine.

 

We manage on 100Ah per day on the 12 volts so are not excessive users of leccy, but do like the washing machine.

I am also trying to do my bit for the environment and in our case more batteries works better than lots of solar.

 

If you convert the whole boat (lights, pumps etc.) to 24V then what's left at 12V, unless you keep this for the engine starter? (only the genny on my boat)

 

24V is perfectly fine up to 5kW or so which more than covers most boats, you only really need 48V if you go beyond this -- for example if you want to go gas-free/all-electric with induction hob/cooker/washer-drier/kettle/toaster/microwave...

 

(I've seen >7kW power draw from the batteries when we were cooking dinner and the washer/drier was running and the kettle was on, but everything was fine with this)

 

But doing this is expensive and very difficult to justify unless you're doing it anyway for 48V electric propulsion (also with a diesel generator), in which case it's free*** because all the hardware is already there.

 

*** meaning you've already paid out a fortune for this, but there's no *extra* cost... 😉

Edited February 14 by IanD

[GUMPY]

6 hours ago, Tony Brooks said:

 

I take the general point but I think incorrect. For as long as I can remember, CAV produced double pole master switches for buses, coaches and vehicles that had to be wired insulated return because of dangerous cargoes. I accept they were not readily available at the local chandler and most boaters would not pay for them.

Maybe I should have said easily available. I know that I would have had a heart attack at the cost.

[dmr]

1 hour ago, IanD said:

 

If you convert the whole boat (lights, pumps etc.) to 24V then what's left at 12V, unless you keep this for the engine starter? (only the genny on my boat)

 

24V is perfectly fine up to 5kW or so which more than covers most boats, you only really need 48V if you go beyond this -- for example if you want to go gas-free/all-electric with induction hob/cooker/washer-drier/kettle/toaster/microwave...

 

(I've seen >7kW power draw from the batteries when we were cooking dinner and the washer/drier was running and the kettle was on, but everything was fine with this)

 

But doing this is expensive and very difficult to justify unless you're doing it anyway for 48V electric propulsion (also with a diesel generator), in which case it's free*** because all the hardware is already there.

 

*** meaning you've already paid out a fortune for this, but there's no *extra* cost... 😉

24volt is affordable and I expect 48 will come down in price soon, but 24 will do fine. We have a lot of 12 volt sockets and stuff that plugs in to them, mostly fans for the hot weather, and I don't want to replace pumps, so staying at 12 volts for the boat circuits is fine. I rarely see more than 10 amps going out so I could go to 24 volts and run the whole boat off a DC-DC converter (or two to give redundancy) but I am quite happy to stick with 12 volts and then have a separate 24 volt bank for the inverter/washing machine.  There was mention up above somewhere of a possible bi-directional DC-DC from Victron, that would be a neat way to link the banks.

Anyway phase 1 of this project is to get a Zeus working with the current 12 volt Trojan bank and see how many amps I can squeeze out of the 100 amp alternator.

[IanD]

1 minute ago, dmr said:

24volt is affordable and I expect 48 will come down in price soon, but 24 will do fine. We have a lot of 12 volt sockets and stuff that plugs in to them, mostly fans for the hot weather, and I don't want to replace pumps, so staying at 12 volts for the boat circuits is fine. I rarely see more than 10 amps going out so I could go to 24 volts and run the whole boat off a DC-DC converter (or two to give redundancy) but I am quite happy to stick with 12 volts and then have a separate 24 volt bank for the inverter/washing machine.  There was mention up above somewhere of a possible bi-directional DC-DC from Victron, that would be a neat way to link the banks.

Anyway phase 1 of this project is to get a Zeus working with the current 12 volt Trojan bank and see how many amps I can squeeze out of the 100 amp alternator.

All the 48V gear is pretty high power amd therefore expensive in absolute terms -- a 5kW 48V inverter is cheaper then a 5kW 24V one but is still pricey. 24V is also widely used in trucks and buses so a lot of gear around, 48V is rare/small volume at the moment but this may change if it gets adopted in cars in the future.

 

The possibly/probably-bidirectional-in-future Victron B2B is 12V (nominal) to 12V (nominal) -- either voltage can be higher or lower but limits are something like 10V-16V IIRC, this is inherently possible with a buck-boost converter.

 

This should also be possible in theory with step up/step down converters (e.g. 12V to 24V or vice versa) but AFAIK none of them do this at the moment, they're all designed to transfer power in one direction only.

[nicknorman]

19 minutes ago, dmr said:

 

Anyway phase 1 of this project is to get a Zeus working with the current 12 volt Trojan bank and see how many amps I can squeeze out of the 100 amp alternator.

 

This will depend entirely on how hot you want to run the alternator!

[dmr]

25 minutes ago, nicknorman said:

 

This will depend entirely on how hot you want to run the alternator!

 

Without major engineering (machine shop stuff) I am stuck with a single V belt and am running a bigger pulley than is ideal in order to control belt slip.

Once I have the option to limit current/field drive I can hopefully go to a smaller pulley to get a bit more cooling, and then do a temperature limit. I am hoping to get a continuous output of about 70 amps. Setting the maximum temperature will be a seat of the pants sort of thing.

In a previous post you did question whether Bluetooth real time monitoring and control was really essential and this is a case where it will be very useful.

 

Another topic for another day is the option of using external rectifier diodes to get a bitmore  ouput without overheating.

[IanD]

42 minutes ago, dmr said:

 

Without major engineering (machine shop stuff) I am stuck with a single V belt and am running a bigger pulley than is ideal in order to control belt slip.

Once I have the option to limit current/field drive I can hopefully go to a smaller pulley to get a bit more cooling, and then do a temperature limit. I am hoping to get a continuous output of about 70 amps. Setting the maximum temperature will be a seat of the pants sort of thing.

In a previous post you did question whether Bluetooth real time monitoring and control was really essential and this is a case where it will be very useful.

 

Another topic for another day is the option of using external rectifier diodes to get a bitmore  ouput without overheating.

 

Have you also considered an external cooling fan/ducting to blow cold air into the alternator?

[nicknorman]

1 hour ago, dmr said:

 

Without major engineering (machine shop stuff) I am stuck with a single V belt and am running a bigger pulley than is ideal in order to control belt slip.

Once I have the option to limit current/field drive I can hopefully go to a smaller pulley to get a bit more cooling, and then do a temperature limit. I am hoping to get a continuous output of about 70 amps. Setting the maximum temperature will be a seat of the pants sort of thing.

In a previous post you did question whether Bluetooth real time monitoring and control was really essential and this is a case where it will be very useful.

 

Another topic for another day is the option of using external rectifier diodes to get a bitmore  ouput without overheating.

I think 70% of maximum is a reasonable target. My Iskra is dual fan (one at each end) and I can run it at around 125A/175A ie 71%, that with a limiting cooling air exit temperature of 90C which is fairly conservative bearing in mind the alternator spec says max AMBIENT temperature of 110C

23 minutes ago, IanD said:

 

Have you also considered an external cooling fan/ducting to blow cold air into the alternator?

He has a "proper" engine room so alternator inlet temperature will be close to ambient with the doors open. Just a moment whilst I convert that to morse code...

[dmr]

9 minutes ago, nicknorman said:

I think 70% of maximum is a reasonable target. My Iskra is dual fan (one at each end) and I can run it at around 125A/175A ie 71%, that with a limiting cooling air exit temperature of 90C which is fairly conservative bearing in mind the alternator spec says max AMBIENT temperature of 110C

He has a "proper" engine room so alternator inlet temperature will be close to ambient with the doors open. Just a moment whilst I convert that to morse code...

 

The engine room can get surprisingly hot in summer, especially if working the engine hard on a river. I think we have hit 40 degrees once or twice though this will be on rainy days when we can't open the sides. This can be quite an issue with proper engine rooms as we sleep in the back cabin and if we boat late into the evening its just too hot for sleeping, though lovely in winter. A couple of fans aimed at the engine is effective (once the engine has stopped).  How hot does it get in "an under the deck" engine 'oil?

This is another reason to get the Zeus with temperature control, better than setting a current limit and assuming the temperature.

 

A long while ago Iskra said a winding temperature of 120 degrees was ok but I would not be too happy with that. I suspect that our alternator is just a smaller version of yours, but in our case dog hairs blocking up the airways is a significant issue.

 

 

[peterboat]

2 hours ago, dmr said:

24volt is affordable and I expect 48 will come down in price soon, but 24 will do fine. We have a lot of 12 volt sockets and stuff that plugs in to them, mostly fans for the hot weather, and I don't want to replace pumps, so staying at 12 volts for the boat circuits is fine. I rarely see more than 10 amps going out so I could go to 24 volts and run the whole boat off a DC-DC converter (or two to give redundancy) but I am quite happy to stick with 12 volts and then have a separate 24 volt bank for the inverter/washing machine.  There was mention up above somewhere of a possible bi-directional DC-DC from Victron, that would be a neat way to link the banks.

Anyway phase 1 of this project is to get a Zeus working with the current 12 volt Trojan bank and see how many amps I can squeeze out of the 100 amp alternator.

I have used a 24 to 12 volt 30 amp DC converter for years with no problems at al, it was a cheap one from ebay.

[nicknorman]

13 minutes ago, dmr said:

 

The engine room can get surprisingly hot in summer, especially if working the engine hard on a river. I think we have hit 40 degrees once or twice though this will be on rainy days when we can't open the sides. This can be quite an issue with proper engine rooms as we sleep in the back cabin and if we boat late into the evening its just too hot for sleeping, though lovely in winter. A couple of fans aimed at the engine is effective (once the engine has stopped).  How hot does it get in "an under the deck" engine 'oil?

This is another reason to get the Zeus with temperature control, better than setting a current limit and assuming the temperature.

 

A long while ago Iskra said a winding temperature of 120 degrees was ok but I would not be too happy with that. I suspect that our alternator is just a smaller version of yours, but in our case dog hairs blocking up the airways is a significant issue.

 

It doesn’t seem to get that hot in the under deck (actually very small under boards compartment of the “modern trad” stern. I think because there are large areas of uninsulated steel in contact with the cut, and when the engine sucks air into the inlet, new air comes in from outside. Being a diesel there is a lot of air going through the engine even at low power. So there is a kind of “forced ventilation”. Still, I suspect it gets to 40C in summer.

[magnetman]

It would be interesting to experiment with ducting using the air intake of the engine to pull cold air across the alternator. Obviously this could have a negative impact on engine performance. Maybe an intercooler would be nice. 

 

35 minutes ago, nicknorman said:

 Being a diesel there is a lot of air going through the engine even at low power. 

Interesting theory. 

 

I would have thought a petrol engine of the same displacement would shift more air as it will tend to have a higher rpm. 

Edited February 14 by magnetman

[cheesegas]

1 hour ago, dmr said:

The engine room can get surprisingly hot in summer, especially if working the engine hard on a river. I think we have hit 40 degrees once or twice though this will be on rainy days when we can't open the sides. This can be quite an issue with proper engine rooms as we sleep in the back cabin and if we boat late into the evening its just too hot for sleeping, though lovely in winter. A couple of fans aimed at the engine is effective (once the engine has stopped).  How hot does it get in "an under the deck" engine 'oil?

This is another reason to get the Zeus with temperature control, better than setting a current limit and assuming the temperature.

 

A long while ago Iskra said a winding temperature of 120 degrees was ok but I would not be too happy with that. I suspect that our alternator is just a smaller version of yours, but in our case dog hairs blocking up the airways is a significant issue.

When I did my lithium install I was concerned about alternator temperature so I installed a sensor with a bit of NodeRed code to manage the temps. However, in reality, it wasn't an issue at all - the air coming in to my cruiser stern narrowboat in winter is pretty cold, and winter is when the alternator will be working hard as there's not much solar. I have two vents in the stern, about 8" by 12" and the batteries' temperature sensor reports temps in the high 30s when the engine is working hard. I was considering putting a fan by one of the vents to pull air through the engine bay as the batteries will appreciate it

 

However, for most of the year (and especially the warmer months!) there's so much solar that if I go for a 7am morning cruise, I don't want to waste diesel throwing 60a into the batteries as the solar will fill it by lunchtime anyway. For that reason, I'm finding I can switch the alternator off around April and then end up turning it on in late Oct. The starter battery is charged by a DC-DC from the leisure, which is activated when the engine is running, shore power is connected or if it hasn't been activated for 14 days which is rare! 

 

I can however see the need for alternator cooling on boats which don't have much solar, or use so much power that the panels can't keep up in summer.

 

I've ordered a Zeus and should have it in the next few days, but won't have the time to fit it for a while. Currently I have a modified Balmar ARS5 on alternator duty which is a bit bodgy!

Edited February 14 by cheesegas

[nicknorman]

21 minutes ago, magnetman said:

I would have thought a petrol engine of the same displacement would shift more air as it will tend to have a higher rpm. 

No, massive difference between a petrol and diesel engine at low power/idle. The petrol engine has the throttle closed, this severely restricts both airflow and fuel - the throttle is typically a butterfly valve that is closed at idle. Very little airflow. This is because the mixture must remain within very close tolerances, so small fuel flow = small air flow.

The diesel engine “throttle” only controls fuel flow. There is no restriction on the air inlet. A diesel doesn’t need or want a stochiometric  mixture. So a 2 litre diesel shifts 2 litres of air every 2 revolutions at idle (roughly).
 

A 2 litre petrol engine at idle shifts a tiny fraction of 2 litres of air every 2 rotations.

[cheesegas]

1 minute ago, nicknorman said:

No, massive difference between a petrol and diesel engine at low power/idle. The petrol engine has the throttle closed, this severely restricts both airflow and fuel - the throttle is typically a butterfly valve that is closed at idle. Very little airflow. This is because the mixture must remain within very close tolerances, so small fuel flow = small air flow.

Also worth noting that because of this, there's a lot more carbon monoxide in petrol exhaust compared to diesels - at low throttle/low load, I seem to remember reading it's something like 50-100% more. All the more reason to run a petrol genny off the boat and downwind!

[magnetman]

I was simplistically thinking a piston moving downwards would be sucking in air. 

Love a bit of education !

[nicknorman]

1 minute ago, cheesegas said:

Also worth noting that because of this, there's a lot more carbon monoxide in petrol exhaust compared to diesels - at low throttle/low load, I seem to remember reading it's something like 50-100% more. All the more reason to run a petrol genny off the boat and downwind!

Yes. Certainly at idle I would have thought a diesel produced virtually no CO. Although 100% more is only twice as much, I would have thought it was much more.

[BEngo]

If you keep away from black smoke (overtorque)  situations, diesels produce very little CO across the speed range.  That is because there is, even at designed full load,  always excess air in order to achieve compression ignition  temperatures.  Plenty of air meens all the injected fuel is properly burned.  The excess air also keeps combustion  things fairly  cool, so there is little NOx.

 

No hydrocarbons, no NOx, No CO.  All very green.  Pity about the PM 10's.

 

N

[peterboat]

24 minutes ago, cheesegas said:

Also worth noting that because of this, there's a lot more carbon monoxide in petrol exhaust compared to diesels - at low throttle/low load, I seem to remember reading it's something like 50-100% more. All the more reason to run a petrol genny off the boat and downwind!

Actually lots of modern diesels have throttles now, quite why I have not bothered to find out, but I did a 3 litre cambelt last week and the butterfly was there. Perhaps its something to do with EGR or DPF regeneration, or performance? Who knows 

14 minutes ago, BEngo said:

If you keep away from black smoke (overtorque)  situations, diesels produce very little CO across the speed range.  That is because there is, even at designed full load,  always excess air in order to achieve compression ignition  temperatures.  Plenty of air meens all the injected fuel is properly burned.  The excess air also keeps combustion  things fairly  cool, so there is little NOx.

 

No hydrocarbons, no NOx, No CO.  All very green.  Pity about the PM 10's.

 

N

Lots of NOx from diesels which is why they have EGRs

[cheesegas]

Just now, peterboat said:

Actually lots of modern diesels have throttles now, quite why I have not bothered to find out, but I did a 3 litre cambelt last week and the butterfly was there. Perhaps its something to do with EGR or DPF regeneration, or performance? Who knows 

Interesting, I didn't know that, I'll have a read. Weirdly, some petrol engines have gone the opposite way with direct injection like a diesel - they don't have a butterfly valve which reduces energy lost in pumping against the closed valve at partial throttle opening.

[dmr]

27 minutes ago, magnetman said:

I was simplistically thinking a piston moving downwards would be sucking in air. 

Love a bit of education !

 

A good analogy is trying to work a bicycle tyre pump with your thumb over the hole, this is exactly what a throttled petrol engine is doing and it wastes a lot of energy, and hence why a diesel is much more efficient.

[peterboat]

4 minutes ago, cheesegas said:

Interesting, I didn't know that, I'll have a read. Weirdly, some petrol engines have gone the opposite way with direct injection like a diesel - they don't have a butterfly valve which reduces energy lost in pumping against the closed valve at partial throttle opening.

No have a look at this.

The petrol engines without throttle seem to be BMW based very strange but they work

 

Edited February 14 by peterboat

[nicknorman]

9 minutes ago, peterboat said:

Actually lots of modern diesels have throttles now, quite why I have not bothered to find out, but I did a 3 litre cambelt last week and the butterfly was there. Perhaps its something to do with EGR or DPF regeneration, or performance? Who knows 

Lots of NOx from diesels which is why they have EGRs

 

Yes this is true, and not just modern diesels. But not the sort of diesels found on narrowboats.

I just asked an AI chatbot why. This is the answer:

• Modern diesel engines may still feature throttle bodies, primarily for emissions control and Exhaust Gas Recirculation (EGR).
• The throttle body’s butterfly valve can be controlled by the ECU (Electronic Control Unit) or a solenoid-controlled vacuum line.
• Under low engine load conditions, the ECU restricts the amount of fresh air (from the turbocharger) entering the intake manifold. This creates a pressure differential, aiding the EGR system by allowing more exhaust gas to be recirculated.
• During engine shutdown, the throttle body acts as an Anti-Shudder Valve (ASV), ensuring a smoother shutdown.

I also asked it why some BMW petrol engines don't have a throttle valve. This was the answer (quite useful these AI things!)

 

Certainly! Some BMW petrol engines are designed without a traditional throttle valve, and here’s why:

1. Valvetronic Technology:

   • BMW employs an innovative system called Valvetronic in certain petrol engines.
   • Unlike conventional throttle bodies, Valvetronic eliminates the need for a butterfly throttle valve.
   • Instead, it electronically adjusts both the lift and timing of the intake valves.

2. How Valvetronic Works:

   • When you press the gas pedal in a Valvetronic-equipped BMW, you’re altering how much the intake valves open.
   • The Valvetronic system varies valve lift instantly, allowing precise control over engine breathing.
   • By eliminating the traditional throttle valve, BMW reduces pumping losses.
   • Pumping losses occur when the throttle restricts airflow during partial load conditions, wasting energy.

3. Benefits of Valvetronic:

   • Improved fuel efficiency: Valvetronic optimizes air intake without relying on a throttle plate.
   • Enhanced power delivery: The system adjusts valve lift dynamically based on driver demand.
   • Drive-by-wire throttle action: Valvetronic operates electronically, providing a seamless response.

4. Production and Impact:

   • Valvetronic-equipped engines are manufactured at BMW’s Hams Hall plant in England.
   • These engines enhance performance, reduce emissions, and contribute to BMW’s reputation for innovation.

In summary, BMW’s Valvetronic technology replaces the traditional throttle valve, resulting in more efficient and responsive petrol engine

[peterboat]

50 minutes ago, nicknorman said:

 

Yes this is true, and not just modern diesels. But not the sort of diesels found on narrowboats.

I just asked an AI chatbot why. This is the answer:

• Modern diesel engines may still feature throttle bodies, primarily for emissions control and Exhaust Gas Recirculation (EGR).
• The throttle body’s butterfly valve can be controlled by the ECU (Electronic Control Unit) or a solenoid-controlled vacuum line.
• Under low engine load conditions, the ECU restricts the amount of fresh air (from the turbocharger) entering the intake manifold. This creates a pressure differential, aiding the EGR system by allowing more exhaust gas to be recirculated.
• During engine shutdown, the throttle body acts as an Anti-Shudder Valve (ASV), ensuring a smoother shutdown.

I also asked it why some BMW petrol engines don't have a throttle valve. This was the answer (quite useful these AI things!)

 

Certainly! Some BMW petrol engines are designed without a traditional throttle valve, and here’s why:

1. Valvetronic Technology:

   • BMW employs an innovative system called Valvetronic in certain petrol engines.
   • Unlike conventional throttle bodies, Valvetronic eliminates the need for a butterfly throttle valve.
   • Instead, it electronically adjusts both the lift and timing of the intake valves.

2. How Valvetronic Works:

   • When you press the gas pedal in a Valvetronic-equipped BMW, you’re altering how much the intake valves open.
   • The Valvetronic system varies valve lift instantly, allowing precise control over engine breathing.
   • By eliminating the traditional throttle valve, BMW reduces pumping losses.
   • Pumping losses occur when the throttle restricts airflow during partial load conditions, wasting energy.

3. Benefits of Valvetronic:

   • Improved fuel efficiency: Valvetronic optimizes air intake without relying on a throttle plate.
   • Enhanced power delivery: The system adjusts valve lift dynamically based on driver demand.
   • Drive-by-wire throttle action: Valvetronic operates electronically, providing a seamless response.

4. Production and Impact:

   • Valvetronic-equipped engines are manufactured at BMW’s Hams Hall plant in England.
   • These engines enhance performance, reduce emissions, and contribute to BMW’s reputation for innovation.

In summary, BMW’s Valvetronic technology replaces the traditional throttle valve, resulting in more efficient and responsive petrol engine

There we go, only issues for the BMW engines is the timing chain is at the rear of the engine, it fails early and scrap the engine!!!

[IanD]

3 hours ago, nicknorman said:

I think 70% of maximum is a reasonable target. My Iskra is dual fan (one at each end) and I can run it at around 125A/175A ie 71%, that with a limiting cooling air exit temperature of 90C which is fairly conservative bearing in mind the alternator spec says max AMBIENT temperature of 110C

He has a "proper" engine room so alternator inlet temperature will be close to ambient with the doors open. Just a moment whilst I convert that to morse code...

Two can play that game -- what's Morse code for "Melted any good CANbus cables recently"? 🙂

Edited February 14 by IanD