First test results Winston vs LiTime

[Chotu]

Originally Posted by sailorboy1

In the end it will come down to whether the Winston cell bank is "better", and if so are they the price multiplier difference "better"

That’s really what it is. It’s about value. Basically what should be carefully analyzed is

$ per AH or KW of charge and discharge cycle

[wholybee]

Originally Posted by sailorboy1

In the end it will come down to whether the Winston cell bank is "better", and if so are they the price multiplier difference "better"

You have to consider the time frame they were purchased. Several years ago, there were far fewer drop-ins, and even buying cells to build your own there were a lot of questions of quality, and a lot of people that got burned buying other than a top end cell from a top tier expensive dealer.

When I built my battery, I came very close to buying 560Ah of EVE cells from a seller that had many positive reviews. The last second, they day I placed the order, I changed to 300Ah of Calb cells from a brick and mortar seller in the US at 2x the cost. Boy am I glad I did, the shipment of EVE cells that mine were to be in was 100% trash. Probably 100 buyers, if they got any cells at all, they were bloated, broken open, or didn't work at all. The seller vanished with everyone's money.

And that is but one story, 5 years ago it was a huge risk to buy the cheaper stuff. Things have shaken out now, and I think there are a lot more cheaper options.

The difference between Winston and LiTime probably won't be known for 15-20 years. LiTime is going to have an inferior BMS, but I think many people go way overkill with the BMS anyway.

[sailorboy1]

Originally Posted by wholybee

You have to consider the time frame they were purchased. When I priced Winston cells just 12 months ago my house bank would have been 4x the cost just for the cells over my Power Queen batteries

And that is but one story, 5 years ago it was a huge risk to buy the cheaper stuff. 5 years takes you back to the stone age far as LFP prices. Even 3 years ago a 400ah set was $2000. 12 months ago I got 400ah for $1319 including shipping and tax. Now those same batteries are 20% less.

Only time will tell. But the expensive batteries don't appear to be coming down.

for 12V 100ah

Victron $832
Battleborn $925
Power Queen $230 (the one I paid $306 for just 11 months ago)

[s/v Jedi]

Some background information:

I have these LiTime batteries: https://www.litime.com/products/liti...00a-bms-5120wh

The reasons I selected these:

- 200A BMS so with two in parallel I can do 400A
- 24V versions so when one dies, I can continue on the other one. They also sell the same size battery as 12V 400Ah and one can put two in series for 24V but that means no redundancy, plus they have parallel cells inside, while mine have 8x 200Ah cells in series.

Compared to the Winston battery, power output is a big difference. At the same capacity, the Winston cells can put out 1,200A continuously compared to the 400A of the LiTime battery bank. But I used a 400A fuse and a 500A switch so I don’t use that power output; it’s not so important for a house battery.

[wholybee]

Originally Posted by sailorboy1

Only time will tell. But the expensive batteries don't appear to be coming down.

for 12V 100ah

Victron $832
Battleborn $925
Power Queen $230 (the one I paid $306 for just 11 months ago)

Agreed. For timeframe, I am not talking about price differences, but quality differences. Right now you can buy a decent LFP for a couple hundred dollars, some off the wall never heard of before brand. 5 years ago, if you bought something other than Winston, Calb, or Sinopoly, from a primary seller (no Alibaba/Aliexpress) there was a very real probability that what you got would not last 2 weeks.

[smac999]

Originally Posted by rslifkin

Cold weather use is one of my concerns, as the boat is typically stored over the winter, so I need to be able to safely show up to the boat, power things up, and plug it in to shore power when I go to work on something during the winter. With the current AGMs it's not a concern. Just plug it in, climb aboard, flip a few switches on and we're good to go. Reverse the process before leaving.

why are you unplging it? run the heaters 24/7 all winter. every boat around here does. though they are also in the water which helps. not sure if your stored means in or out ot water.

[rslifkin]

Originally Posted by smac999

why are you unplging it? run the heaters 24/7 all winter. every boat around here does. though they are also in the water which helps. not sure if your stored means in or out ot water.

Stored out of the water and indoors. The marina's insurance doesn't like unattended boats plugged in to power in the storage building. So unless I switch to storing outside (in which case I'd need to get winter covers for the boat or eat the cost of shrink wrap every year), the boat can't stay plugged in all winter (which is what makes the battery situation challenging). There's basically no draw while the boat is sitting unplugged though (only things that I don't cut the power to are the Smartshunt and the stereo memory). So I don't necessarily care about being able to do much charging when I'm there, it's more a matter of making sure I don't drain the batteries too far or damage them while I'm at the boat and have things powered up.

[s/v Jedi]

Another very interesting observation: during high amp charging (24V 140A) the Winston battery accepts much more than the LiTime, but under low amp charging afterwards (from solar) the LiTime accepts more.

My theory: the impedance of the Winston battery is much lower because there isn’t a MOSFET based BMS adding resistance. When switching off the big charger, the LiTime is lagging in SOC and the FETs have less resistance at the low current.

Other thoughts?

[wholybee]

Originally Posted by s/v Jedi

Another very interesting observation: during high amp charging (24V 140A) the Winston battery accepts much more than the LiTime, but under low amp charging afterwards (from solar) the LiTime accepts more.

My theory: the impedance of the Winston battery is much lower because there isn’t a MOSFET based BMS adding resistance. When switching off the big charger, the LiTime is lagging in SOC and the FETs have less resistance at the low current.

Other thoughts?

I am sure the FETs affect charging as you figure. Two other things. The IR of a cell changes with SOC. The cells certainly have different curves for this. And second, if the Winston accepts more current at first, the Winston will rise in voltage faster. When the SOC reaches the steeper part of the voltage curve, the LiTime will accept more current as the voltages come back together.

I suspect, but could be wrong, that they ultimately would reach 100% SOC at the same time. With whatever battery was as a higher SOC progressively accepting less current until they are both fully charged.

[s/v Jedi]

Originally Posted by wholybee

I am sure the FETs affect charging as you figure. Two other things. The IR of a cell changes with SOC. The cells certainly have different curves for this. And second, if the Winston accepts more current at first, the Winston will rise in voltage faster. When the SOC reaches the steeper part of the voltage curve, the LiTime will accept more current as the voltages come back together.

I suspect, but could be wrong, that they ultimately would reach 100% SOC at the same time. With whatever battery was as a higher SOC progressively accepting less current until they are both fully charged.

Yes they do reach 100% at the same time. Interestingly I have seen LiTime deliver more amps to loads a couple of times. It seems to have different resistance for load vs charge.

[CaptainRivet]

Originally Posted by wholybee

You have to consider the time frame they were purchased. Several years ago, there were far fewer drop-ins, and even buying cells to build your own there were a lot of questions of quality, and a lot of people that got burned buying other than a top end cell from a top tier expensive dealer.

When I built my battery, I came very close to buying 560Ah of EVE cells from a seller that had many positive reviews. The last second, they day I placed the order, I changed to 300Ah of Calb cells from a brick and mortar seller in the US at 2x the cost. Boy am I glad I did, the shipment of EVE cells that mine were to be in was 100% trash. Probably 100 buyers, if they got any cells at all, they were bloated, broken open, or didn't work at all. The seller vanished with everyone's money.

And that is but one story, 5 years ago it was a huge risk to buy the cheaper stuff. Things have shaken out now, and I think there are a lot more cheaper options.

The difference between Winston and LiTime probably won't be known for 15-20 years. LiTime is going to have an inferior BMS, but I think many people go way overkill with the BMS anyway.

I highly advise you to take the EVE304AH, much better cells with good terminals compared to the tiny M6 studs and terminal surface which you permanently risk to strip the thread as it’s 6mm, means hardly enough to grab properly. Some vendors weld on 8mm, that’s the much better choice if you really wanna get the 280AH but terminal surface gets really small then.
Yes I know new 280 are rated 6000 cycles while 304 „only“ 4000 but in real life no difference other then 304 can deal with higher C-Rate much better then 280 ones.

[CaptainRivet]

Originally Posted by s/v Jedi

Yes they do reach 100% at the same time. Interestingly I have seen LiTime deliver more amps to loads a couple of times. It seems to have different resistance for load vs charge.

Li time has EVE cells if I remember right. My Lishen are quite equal to EVE and they have the lowest resistance in the 75 to 90% SOC area and the highest low down at below 25% while Winston have a quite linear lower resistance overall.
Exactly what Jedi described.i assume that gets even more amplified by the FETs behavior of BMS.
My experience so far:
As long as you pamper the cells with around 0.2C usage and in warm climates the Winston’s cannot really show their capabilities and value.
But if you take a 200 or 300AH bank on eg small boat where you can simply fit more and do electric galley with a 3kw inverter and even have windlass and maybe even starter running via Winston then they can really show the difference in quality or if we get to more extreme temperatures like below 0 or above 40 degrees Celsius or cycling them extremely hard with high c-Rates loads and charge

Another thing to take into account if you parallel 6x100AH of the cheap droppins the first battery and inside the first and last cell get massively more load then the others and if you run here a 3kw inverter and 1200W windlass that 1st and last cell in the 1st battery will have a short life as overloaded massively, but most likely before the FETs in the BMS will burn through. That’s the real reason behind them stating not more then eg 4 in parallel are allowed…so if you go to 4 parallel the first one with first and last cell will be seriously stressed. And that’s worse if cells inside the battery are paralleled means a 200Ah in 2P4S or even worse if 4P4S with 50AH cells. That’s why it’s highly recommended to buy the battery with the biggest capacity cells and 1p4S or 8s setup inside. That’s also why the best house setup for a boat is 2 or max 3 parallel batteries or cellpacks. 2 because of redundancy and 3 because of capacity as the biggest but economically AH per buck cells are all in the 300AH range. Best practice is connect each battery (with a proper battery fuse class T or NH) directly to the busbar (and not terminal to terminal) and if 3 or 4 the middle cells first/closest to the connection point of the main power cable.
But for simplicity (in >=400AH range) you can simply get 400,700 or 1000AH Winston cells in a 1p4 or 8s config as they are extremely reliable and robust so you can run them (also in emergency) just with a battery monitor that does LCV and HCV cut off. highly advisable to use a BMS in relation to what this cells cost but I know serval systems running >10years without BMS in 12V setup on Winston.

[s/v Jedi]

People think the BMS is most important for balancing the cells. With Winston cells I didn’t have to balance yet and it is year 4 now.

[CaptainRivet]

Originally Posted by s/v Jedi

People think the BMS is most important for balancing the cells. With Winston cells I didn’t have to balance yet and it is year 4 now.

True with Winston but if you ever have to i highly recommend top balance them to 3,65 or even 3,70V.
They really need the absolute top of the steep curve due to the yittrium to get the optimal top balance.
Catnewbee with 1000A Winston cell was balancing to 3,55V which throwed them off so he needed an active balancer going to 3,65V to achieve that, sure reason he needs the active balancer he is using them in 1p4S but regularly with massive 5-7kw inverter load which is up to (630A (average)*1.41)/88% efficiency inverter=935A+ other house loads.
3,55V is absolute fine for pure Lifepo4 like in all the budget dropins.

I think you found the best solution for buck but also reliability of a house bank, have one high quality battery made of quality cells and quality non FET BMS that can suit your usage of 1.5 or 2 days and then add cheap dropins to extend capacity and take the load off high quality one. Instead cheap dropins you can also use budget 280 or 304AH cells, even in 2 o 3p4/8S that’s cheaper then dropins and you generally get better quality cells+BMS.
I will start look around for good deals on 4x 150, 200 or 300AH Winston cells

You could even put starter and windlass just directly to the high quality one so you have a hybrid starter and house bank without risking to fry the FET BMS in the cheap dropins. Hybrid banks make really sense in cats where one hull you start from house while in the other you have dedicated starter battery, maybe a bit more capacity then just needed for starting eg cooling truck or hybrid lead so it works as backup bank too. I would and will use LTO for that starter/backup bank.

[Pete7]

Originally Posted by Kettlewell

This is a question I have too. My current LA batteries stay on solar charge over the winter and I can just use them normally when visiting the boatyard, even if it is below freezing. One thought might be to keep a standard LA hooked up somewhere in the system for use when it is cold, and just let the Lithium bank hibernate over the winter. One important reason I have found to keep the batteries hooked up is in case of flooding due to something going wrong. I have seen several boats flooded over the winter because a deck fitting or a cockpit drain let go and water just kept coming in with no bilge pump hooked up. Not every boat has a bilge plug that can be pulled, and that tiny hole sometimes just gets plugged or freezes closed.

This is how we run our hybrid bank. When not on board LFP batteries isolated at a safe state of charge, somewhere between 50 - 80%. The lead-acid FLA Trojans remain connected and power the bilge pump whilst being charged by solar. The engine start AGM has a jumper cable to add in occasionally just to give it a boost.

Plus in the event of a complete shutdown from the BMSs, we will still have some power for a while. Just don't tell ABYC or you will be ex-communicated

Pete