First test results Winston vs LiTime

[s/v Jedi]

I have started testing my two lithium battery banks:

Bank A = 8x Winstron 400Ah cells in series

Bank B = 2x LiTime 200Ah 24V batteries in parallel

So bank A is considered the Rolls Royce of batteries and bank B the lowest price cheap drop-in’s. But both are of the same capacity.

When I put them both online there was a 0.4V difference between them and this resulted in a 30A current for a minute or so followed by a couple minutes of 20A etc.

Two days in and now I am running A/C on inverter so high load and look how they split the load, near perfect and they can’t even be really balanced yet!

I hope to collect lots of data in the coming months

[s/v Jedi]

Here is absorption charging further balancing the batteries

[wholybee]

Good stuff. I am very interested in your thoughts after several months.

[barcoMeCasa]

Considered saving all the data to a database?
Need a windows or linux computer, couple of serial/usb adaptors & some time to click a mouse for a little while.
https://github.com/SignalK/vedirect-serial-usb

Really is night and day though, like looking into a dark room though a dirty window compared to opening the door & turning on the light.
Like 23mV voltage drop as the fridge kicks in during the top knee can mean a 30% reduction in current going in.
Data is great if you have enough power to leave a machine running full time. ��

[Chotu]

Can't wait to see. I have the LiTime batteries with nothing to compare them against and though I don't have any carefully collected quantitative data, they have certainly been running my boat flawlessly with a 100-160AH nightly draw on a 400AH bank.

In the summer they went back to 100% SOC each day via 30-ish A of solar input (14.2A cutoff voltage - a little high). Now, I'm mostly on generator and I'm taking them all the way down for 3 days, then running the generator for a few hours every third day or so to bring them back up with 90-ish A of charging input. 14.4 cutoff voltage on the LiFePO4 controller for the AC charger from the generator, which is way high, but I manually stop it before this usually. Once in a while I forget and it hits the BMS at 14.4 and gets cut off by that. This is modest usage without even being careful about high voltage.. Already over a year on them. No delectable change in performance yet with basic, simple usage and measurement.

I don't know what the outcome will be years down the line, but just like my motorcycle, Chinese things sure are better than American things in value now. Times have changed a lot. I’ve also had my 3 Vevor diesels heaters running 24/7 for weeks and weeks. We will se about those as well

[s/v Jedi]

Originally Posted by barcoMeCasa

Considered saving all the data to a database?
Need a windows or linux computer, couple of serial/usb adaptors & some time to click a mouse for a little while.
https://github.com/SignalK/vedirect-serial-usb

Really is night and day though, like looking into a dark room though a dirty window compared to opening the door & turning on the light.
Like 23mV voltage drop as the fridge kicks in during the top knee can mean a 30% reduction in current going in.
Data is great if you have enough power to leave a machine running full time. ��

All data is logged to the Victron portal, which I will share. The problem now is that my setup isn’t complete yet so logging is incomplete; I am not logging bank B yet.

[barcoMeCasa]

Originally Posted by s/v Jedi

All data is logged to the Victron portal, which I will share. The problem now is that my setup isn’t complete yet so logging is incomplete; I am not logging bank B yet.

[Jimbo2010]

What are the specs on the AC unit?

[s/v Jedi]

Originally Posted by Jimbo2010

What are the specs on the AC unit?

It’s an old CruiseAir 18kBTU with reverse heat 24kBTU. A power hog.

I am running it off 2x Victron Multiplus 3000 in parallel. The Multiplus as well as the A/C units are all 240V 60Hz.

[carstenb]

Interesting - we just installed 600Ah of Litimes 12V mini 100Ah.

They warranty these for >4000 cycles which means 10 years to me. Cost of the batteries - 6 x $259 or $1554. Really close to the same price as some AGM's

we have no idea what it is like to have 600Ah available - be fun to see how this works out. So far our meters have not shown anything below 13.2V.

Big test will come when make a passage and run everything throughout the night.

[rslifkin]

At this point, it seems like the better drop ins are at least pretty decent batteries. The big thing between different drop ins and a custom build is mostly in the BMS (both current capacity and communications features) it seems.

[s/v Jedi]

Originally Posted by rslifkin

At this point, it seems like the better drop ins are at least pretty decent batteries. The big thing between different drop ins and a custom build is mostly in the BMS (both current capacity and communications features) it seems.

There is a big difference in the quality of the cells. A LiTime battery has cells of the Eve class while diy builds can use cells like Winston, who even allows cold weather charging by doping the electrolyte with Yttrium so they are actually LiFeYPO4.

But for use as house batteries I think the LiTime brand is okay. Will Prowse reports are favorable but there was a lot of negative comments on the forum so I decided to grab a sale deal and get a couple to form a bank that can be directly compared to my Winston battery and show results here.

[rslifkin]

Originally Posted by s/v Jedi

There is a big difference in the quality of the cells. A LiTime battery has cells of the Eve class while diy builds can use cells like Winston, who even allows cold weather charging by doping the electrolyte with Yttrium so they are actually LiFeYPO4.

But for use as house batteries I think the LiTime brand is okay. Will Prowse reports are favorable but there was a lot of negative comments on the forum so I decided to grab a sale deal and get a couple to form a bank that can be directly compared to my Winston battery and show results here.

Agreed, the cells available to use for DIY stuff are better than what goes into the drop-ins. But at the same time, it seems like the better drop-ins are using good enough stuff that in most use cases, there's not much to gain. And some of the drop ins have heating pads tied into the BMS to mitigate the cold weather concerns.

I've been going back and forth on which approach will be better for an eventual LFP upgrade for my boat, but I haven't been able to settle on a definitive answer yet between a DIY build or something like the Epoch drop-ins. 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.

[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"

[Kettlewell]

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.

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.