What would you do?

[grizzzman]

Hi ya native pepper
Is this the device you speak of? https://www.aliexpress.com/store/produc ... 27736.html If so it looks like you would need to disconnect it during storage?

Thanks

I am testing these at the moment, can't leave them connected to a battery that isn't being charged regularly as they will flatten the battery. We are in the process of designing a unit to turn these balances on only when required, that way they don't hide a problem that would be easy to see without the balancers. Better to sort the problem before it becomes so big the balancer can't contain it, by that stage the problem may well be serious where early intervention would have solved the issue with no damage done.

T1 Terry

Hi ya Terry
Thanks for the response. Based on the info and assuming there built well seems like a good way to go. I realize that you are testing but what is you're opinion up to this point? Seems that constant equalizing is not needed often in low C use. What is your opinion Terry?
Thanks

[grizzzman]

I have a few question's if you don't mind Terry. When the battery is in storage (between trips) during the summer could be subject to 48 C temps when parked in the sun. This would happen during the week and to a lesser degree the trailer would do the same. In the winter here can get as cold as -23 C (thank goodness not often) I think to solve that would be to pull the packs in the winter but to pull and install packs every week during the summer would...... Well........suck can the packs handle the temps? I like the idea of a pack in the tug but wouldn't it require two bms ? One for the tug and one for the trailer?

Thanks Terry

Yes, a BMS for each battery, The battery would need to be inside the trailer if -23*C was experienced regularly while in full use, I sure wouldn't want to be there The 48*C is within their capabilities. Winston Batteries say their cells can operate between -48*C and 85*C both charging and discharging, but the loads would need to be gentle I would think, maybe 0.1CA or 10 amps per 100Ah capacity either way to avoid localised cell heating. The heat produced could equalise throughout the cell at a low load/charge rate and once warmed there would be no problem regarding load. A temp sensor between the cells would give a good indication of the heat spread throughout the cell, just on the terminal bolt will indicate very little due to the way the cells are built, nothing like the way lead acid batteries are constructed.

T1 Terry

It was -13 C this morning, how's that? OK looks like temps are do able. Also a good idea is temp sensors on the side of the cells, makes since. I take it the real heat is in the pouches them selfs.

Thanks Terry

[native pepper]

Hi ya native pepper
Is this the device you speak of? https://www.aliexpress.com/store/produc ... 27736.html If so it looks like you would need to disconnect it during storage?

Thanks

I am testing these at the moment, can't leave them connected to a battery that isn't being charged regularly as they will flatten the battery. We are in the process of designing a unit to turn these balances on only when required, that way they don't hide a problem that would be easy to see without the balancers. Better to sort the problem before it becomes so big the balancer can't contain it, by that stage the problem may well be serious where early intervention would have solved the issue with no damage done.

T1 Terry

The equalisers I have, haven't flattened any of my packs so far. When first connecting them, thought that may be the case, but once they have settled in they seem fine. Can understand if you had a bad cell that keeps losing its energy, but other than that, no idea.

My portable pack hasn't been used for about 4 days and it sat at 13.22v after pumping out the boat. It was still sitting at 13,22v this arvo before using it to lift 20lt drums of oil up into the centrifuge tank, have to make fuel this arvo, we are heading up north tomorrow to pick up dual axle trailer. Our 10x5ft single axle is looking very tired and can't carry the weight of the band, bikes and next year a centrifuge. we have a big year next year.

I'm interested to know what sort of problem you think they will cover up, as they transfer energy from one cell, or line to another they should keep all lines in good condition. Using them to my mind would stabilise any differences and keep them all nice and even, so any cell that gets out of whack with the rest, would be equalised and wouldn't suffer.

Wouldn't a dying cell show up quickly with the equalisers, as they would be constantly moving energy around and that would show up quickly on the cell voltage gauges. Mind you I'm just guessing here and probably haven't thought out what else they could cover up, which is probably outside my understanding.

[T1 Terry]

Hi ya Terry
Thanks for the response. Based on the info and assuming there built well seems like a good way to go. I realize that you are testing but what is you're opinion up to this point? Seems that constant equalizing is not needed often in low C use. What is your opinion Terry?
Thanks

Been busy repairing the patio roof ready for Christmas so been off the air for a few days. We had the big white elephant the NBN installed yesterday, still isn't up and running, would have been a good thing if this govt had installed the system the way it was designed but the botched up mess they have now will cost a fortune to fix, but that is another story.

Properly designed from multiple cells in parallel, strapped and properly condition charged/balanced before their first use and quality cells will remain in balance. Balancing becomes an issue with 24v system and even more with 48v systems, 12v systems don't suffer the problems so a full time active balancing system whether wasting energy or transferring energy from the high cell to the low cell is not really needed. The cells will stay in balance without any form of balancer fitted.... unless there is a problem, then the balancer will hide the problem. Basically, if a 12v system requires a balancer to remain in balance and would go out of balance without it, the is a problem with the system that needs to be identified and fixed.

T1 Terry

[T1 Terry]

I have a few question's if you don't mind Terry. When the battery is in storage (between trips) during the summer could be subject to 48 C temps when parked in the sun. This would happen during the week and to a lesser degree the trailer would do the same. In the winter here can get as cold as -23 C (thank goodness not often) I think to solve that would be to pull the packs in the winter but to pull and install packs every week during the summer would...... Well........suck can the packs handle the temps? I like the idea of a pack in the tug but wouldn't it require two bms ? One for the tug and one for the trailer?

Thanks Terry

Yes, a BMS for each battery, The battery would need to be inside the trailer if -23*C was experienced regularly while in full use, I sure wouldn't want to be there The 48*C is within their capabilities. Winston Batteries say their cells can operate between -48*C and 85*C both charging and discharging, but the loads would need to be gentle I would think, maybe 0.1CA or 10 amps per 100Ah capacity either way to avoid localised cell heating. The heat produced could equalise throughout the cell at a low load/charge rate and once warmed there would be no problem regarding load. A temp sensor between the cells would give a good indication of the heat spread throughout the cell, just on the terminal bolt will indicate very little due to the way the cells are built, nothing like the way lead acid batteries are constructed.

T1 Terry

It was -13 C this morning, how's that? OK looks like temps are do able. Also a good idea is temp sensors on the side of the cells, makes since. I take it the real heat is in the pouches them selfs.

Thanks Terry

The Winston cells aren't actually made up out of pouches, there is a single but rather long sheet of separator material woven between each positive and negative plate, so the heat spreads through the cell. The centre layers of the cell are the most likely to heat more than the outer layers as there are more heat producing layers between them and the side wall that dispenses the heat build up.
Each positive plate is an extremely thin sheet of aluminium coated on both sides with a micro mm spray of lithium yttrium ferrous phosphate and all the positive sheets have a tag at one end and all these tags are bolted to a block of aluminium that is attached to the top of the cell. This is the bit that looks like the positive terminal of any other battery that has bolt on terminals, but that is the only thing in common.
Each negative plate is a very thin sheet of copper, micro thin layer of graphite sprayed on each side, a tab on each plate and these are bolted to a block of copper fixed to the cell top. This looks like the normal negative terminal on any other battery, but the give away is the negative is copper and the positive is aluminium.
There is very little electrolyte in each cell, just enough to wet the material in each cell but not enough to slosh about so the cell needs to be compressed to stop the sides from bulging as there would not be enough electrolyte in the cell to fill this greater area and still keep the plates soaked in electrolyte. No electrolyte connection through the separator between the positive and negative plate and no ion exchange, so no storage or energy release from that part of the plate.
So it is important to keep the cells compressed flat on the large area faces and as you might now understand, by the time the heat has transferred through that thin tab on each plate and heated the block of metal, the damaged over heating causes would have already occurred in the lower and centre areas of the cell before that heat was transferred to the block of metal that acts as a terminal, so sensing the heat at the terminal will only tell you that damage has occurred where you actually need to know before damage does occur.

T1 Terry

[grizzzman]

Hi ya Terry
Thanks for the response. Based on the info and assuming there built well seems like a good way to go. I realize that you are testing but what is you're opinion up to this point? Seems that constant equalizing is not needed often in low C use. What is your opinion Terry?
Thanks

Been busy repairing the patio roof ready for Christmas so been off the air for a few days. We had the big white elephant the NBN installed yesterday, still isn't up and running, would have been a good thing if this govt had installed the system the way it was designed but the botched up mess they have now will cost a fortune to fix, but that is another story.

Properly designed from multiple cells in parallel, strapped and properly condition charged/balanced before their first use and quality cells will remain in balance. Balancing becomes an issue with 24v system and even more with 48v systems, 12v systems don't suffer the problems so a full time active balancing system whether wasting energy or transferring energy from the high cell to the low cell is not really needed. The cells will stay in balance without any form of balancer fitted.... unless there is a problem, then the balancer will hide the problem. Basically, if a 12v system requires a balancer to remain in balance and would go out of balance without it, the is a problem with the system that needs to be identified and fixed.

T1 Terry

Glad that you are getting ready for Christmas Internet? Problems suck I understand balancing but am unclear about conditioning?

Thanks

[grizzzman]

Yes, a BMS for each battery, The battery would need to be inside the trailer if -23*C was experienced regularly while in full use, I sure wouldn't want to be there The 48*C is within their capabilities. Winston Batteries say their cells can operate between -48*C and 85*C both charging and discharging, but the loads would need to be gentle I would think, maybe 0.1CA or 10 amps per 100Ah capacity either way to avoid localised cell heating. The heat produced could equalise throughout the cell at a low load/charge rate and once warmed there would be no problem regarding load. A temp sensor between the cells would give a good indication of the heat spread throughout the cell, just on the terminal bolt will indicate very little due to the way the cells are built, nothing like the way lead acid batteries are constructed.

T1 Terry

It was -13 C this morning, how's that? OK looks like temps are do able. Also a good idea is temp sensors on the side of the cells, makes since. I take it the real heat is in the pouches them selfs.

Thanks Terry

The Winston cells aren't actually made up out of pouches, there is a single but rather long sheet of separator material woven between each positive and negative plate, so the heat spreads through the cell. The centre layers of the cell are the most likely to heat more than the outer layers as there are more heat producing layers between them and the side wall that dispenses the heat build up.
Each positive plate is an extremely thin sheet of aluminium coated on both sides with a micro mm spray of lithium yttrium ferrous phosphate and all the positive sheets have a tag at one end and all these tags are bolted to a block of aluminium that is attached to the top of the cell. This is the bit that looks like the positive terminal of any other battery that has bolt on terminals, but that is the only thing in common.
Each negative plate is a very thin sheet of copper, micro thin layer of graphite sprayed on each side, a tab on each plate and these are bolted to a block of copper fixed to the cell top. This looks like the normal negative terminal on any other battery, but the give away is the negative is copper and the positive is aluminium.
There is very little electrolyte in each cell, just enough to wet the material in each cell but not enough to slosh about so the cell needs to be compressed to stop the sides from bulging as there would not be enough electrolyte in the cell to fill this greater area and still keep the plates soaked in electrolyte. No electrolyte connection through the separator between the positive and negative plate and no ion exchange, so no storage or energy release from that part of the plate.
So it is important to keep the cells compressed flat on the large area faces and as you might now understand, by the time the heat has transferred through that thin tab on each plate and heated the block of metal, the damaged over heating causes would have already occurred in the lower and centre areas of the cell before that heat was transferred to the block of metal that acts as a terminal, so sensing the heat at the terminal will only tell you that damage has occurred where you actually need to know before damage does occur.

T1 Terry

Wooow NOW that was a education on cell construction! Thank you for explaining the long term benefit of strapping the cells. It is clear you have spent lots of time on this passion and it shows. I hope you don't mind my question's?

[JohnM]

"The biggest problem we have over here, is every second person has his ideas on how things should be done. Realising we have different power usage and travel modes."

True, but don't you think it may be beneficial to get differing points of view? I like you're idea of a DC to DC charger. That tech is not real common here,

This was the point I was trying to make, my needs are different to yours and to others, there are only a handful of people I know that travel as I do.
Ten years ago solar on vans was in its infancy, some had their own barrows they were pushing, and others were just trying to get something that worked. Some drove all day and only parked at night and then moved on in the morning, others parked as long as the could before moving on. Some, like us, only drove a short distance before pulling up, some depended on the output of the motor to charge batteries, others relied mainly on solar for their power, but have secondary means of charging the battery,
I have developed my system over ten years, to suit us, and I am trying to give my insight as to what I have done, and why. I do not intend to belittle any other ideas and like you said it is beneficial to see other ideas, this is how I developed my own system, be listening and reading other peoples experiences, and ideas and adapting those ideas to suit my purposes.
We have solar as our primary power source, Dc to DC chargers as our secondary method, Ac to DC chargers, powered from 1 kw inverter generator as a back up and finally the same chargers powered from shore power in an emergency.The starter battery have a similar charging regime, solar, engine charge, and generator, they can also be charged via the inverter, from the house batteries, if we get stuck.
What I tried to achieve was redundancy, that is every charge system has a back up with the last alternative being shore power.

[grizzzman]

If you don't mind my asking? How often do use you're gen-set?

Thanks

[T1 Terry]

Hi ya Terry
Thanks for the response. Based on the info and assuming there built well seems like a good way to go. I realize that you are testing but what is you're opinion up to this point? Seems that constant equalizing is not needed often in low C use. What is your opinion Terry?
Thanks

Been busy repairing the patio roof ready for Christmas so been off the air for a few days. We had the big white elephant the NBN installed yesterday, still isn't up and running, would have been a good thing if this govt had installed the system the way it was designed but the botched up mess they have now will cost a fortune to fix, but that is another story.

Properly designed from multiple cells in parallel, strapped and properly condition charged/balanced before their first use and quality cells will remain in balance. Balancing becomes an issue with 24v system and even more with 48v systems, 12v systems don't suffer the problems so a full time active balancing system whether wasting energy or transferring energy from the high cell to the low cell is not really needed. The cells will stay in balance without any form of balancer fitted.... unless there is a problem, then the balancer will hide the problem. Basically, if a 12v system requires a balancer to remain in balance and would go out of balance without it, the is a problem with the system that needs to be identified and fixed.

T1 Terry

Glad that you are getting ready for Christmas Internet? Problems suck I understand balancing but am unclear about conditioning?

Thanks

The conditioning is to make cells made for electric vehicle use suit long cycle life house battery use. Even though they are the same cells the use intended is at opposite ends of the scale, EV use requires big amps (up to 500 amps per 100Ah capacity) discharge to near empty and fully recharged at a controlled rate, the trade off is cycle life but still far better than the lead acid alternative.
On the other side house batteries only require relatively small discharge rates (50 amps per 100Ah is usually about the max) a varied recharge rate generally from solar, no requirement to return to 100% recharged and very rarely 100% capacity discharged often floating between 60% and 90% capacity even during the day charging period. Without conditioning the cells the cycle life will not be much better than EV use, although the high current isn't an issue that made them past their use by date for EV use so still have some life remaining as house batteries they have still suffered seriously depleted capacity. The death by internal build up between the plates causing a shorted cell is still there so cycle life is reduced even though the cells never saw high current discharge use. This is the problem the "experts" with lead acid battery interests are using to put down lithium batteries as a replacement for lead acid. Sadly there will be quite a few cases of exactly that happening because those jumping on the band wagon to sell lithium systems haven't done the hard yards in research but merely skimmed the surface and think they know all there is to know about.
Condition charging was first used for satellite and space use, although there is some dispute regarding the chemistry of the Mars Rover lithium cells, these were condition charged and are still operating after 11 yrs even though they went through a full shut down deep discharge when the solar panels were covered in dust. They recharged, turned back on and away it went again.

T1 Terry