Posted December 31, 20213 yr Following on from various conversations with people telling me to take the manufacturer's warranties and info with a pinch of salt, let's try draw some real world conclusions on the life expectancy / cycle life of Lithium Phosphate batteries. I'm especially interested in the veterans on the forum who've probably been running theirs for a number of years. Please reply to this thread with the following information: Battery Brand/Model: Installation Date: Cycles: Performance: (add your comments here) So mine would be: Battery Brand/Model: Fusion 4.8kwh Installation Date: October 2021 Cycles: 70 Performance: no observable degradation
December 31, 20213 yr Battery Brand/Model: Pylon US3000B (x8) Installation Date: Jan 2020 Cycles: 270 Performance: Very good. Remaining capacity (SOH) is reported as 97.3% by BMS. This is a calculated value - the Pylon BMS (firmware 2.8) reduces remaining capacity by 0.1% for every 740Ah (equivalent to 10 complete discharges). This will probably flatten out later.
January 1, 20223 yr Battery Brand/Model: CALB cells, mixture of 160 Ah and 100 Ah Installation Date: December 2016 Cycles: Unknown. About 5 years (1800 days) of partial (50% to 80% DOD) cycles. Performance: SOH about 55%. Cells manufactured mid 2009 (12.5 calendar years old). Some are ex-EV following a high current incident. The majority of cells are from an "EV kit" that was never used. Charged to 3.45 VPC, floated at 3.36 VPC. Never discharged beyond 80% DOD (20% SOC), or below 3.21 VPC. Home-made BMS. BMS disconnects charge sources or loads if single cell voltage is too high or too low. Max load about 0.31C (of nominal capacity; that's about 0.57C using present capacity). Considering the hard life of some cells, and the considerable calendar age, I think they're doing OK. Edited January 1, 20223 yr by Coulomb
January 1, 20223 yr 4 hours ago, Coulomb said: Battery Brand/Model: CALB cells, mixture of 160 Ah and 100 Ah Installation Date: December 2016 Cycles: Unknown. About 5 years (1800 days) of partial (50% to 80% DOD) cycles. Performance: SOH about 55%. Cells manufactured mid 2009 (12.5 calendar years old). Some are ex-EV following a high current incident. The majority of cells are from an "EV kit" that was never used. Charged to 3.45 VPC, floated at 3.36 VPC. Never discharged beyond 80% DOD (20% SOC), or below 3.21 VPC. Home-made BMS. BMS disconnects charge sources or loads if single cell voltage is too high or too low. Max load about 0.31C (of nominal capacity; that's about 0.57C using present capacity). Considering the hard life of some cells, and the considerable calendar age, I think they're doing OK. @Coulomb Just one question, how important is the cells temperatures in terms of it's life span? I've been monitoring mine with a hawk eye and in my case they can go up to about 34 degrees C, attached dashboard of my cells temperature in the last 7 days 100 AH -- 5.1 KW/h --- 51.2 V --- LBSA Battery.
January 1, 20223 yr 2 minutes ago, Bobster said: I win Nah! The goal is to find the OLDEST LFP battery. Quote Installation Date: December 2016 Mine wins, so far 😜
January 1, 20223 yr 59 minutes ago, Antonio de Sa said: how important is the cells temperatures in terms of its life span? Pretty important. Basically, all chemical reactions, including the ones that degrade the battery cells, happen about twice as fast with each 10°C rise in temperature. So life at 35°C is roughly halved compared to life at 25°C.
January 1, 20223 yr 9 minutes ago, Coulomb said: Pretty important. Basically, all chemical reactions, including the ones that degrade the battery cells, happen about twice as fast with each 10°C rise in temperature. So life at 35°C is roughly halved compared to life at 25°C. Thanks for the feedback. Difficult to achieve that as the ambient temperature in summer peaks at +_ 32 and a min of about 23 degrees C in my house.
January 1, 20223 yr Battery Brand/Model: 4x Pylontech 3000's Installation Date: 1 June 2019 (Production date: 8/3/2019) Cycles: 423 (as per BMS) Performance: have not noticed any degradation
January 3, 20223 yr @Tariq, does not show SOH. Will sometime hook up the laptop to the batteries and get it.
January 5, 20223 yr Built a Battery as one of my first in Nov 2015 and installed . 10Kwh Been cycling to 80% sometimes 90% since then running an Orion BMS (hate them ) unknown cycles will check when i get around to the client this year . Cells are Sinopoly .! My inception back when Elon first came out with his cleverness i decided to give it and try and have not looked back since . Now designed our own BMS systems that are much easier to work with ...
January 6, 20223 yr On 2022/01/03 at 11:53 AM, JacquesVDM said: @Tariq, does not show SOH. Will sometime hook up the laptop to the batteries and get it. How do you do that? Connect through RS232, then what? How do you extract useful information from it? All batteries different or is there a common standard? Apologies for the many questions ...
January 10, 20223 yr @Scubadude, Yes through RS232 and then using the "BatteryView" software to get info of the batteries. Just search for "BatteryView" on this forum for the software.
January 10, 20223 yr This post deviates from the topic, however I am interested in how fast the lithium batteries "deteriorate". My 2 x US3000 pylontech were 2 years old on 7 Jan 2022. In December I noticed the SOH = 99% (after 23 months of use) based on data from Goodwe ES 4.6 At the moment DOD while on grid set at 5% to have maximum reserve in case of power failures, which happen frequently in our town. If above results can be extrapolated in a linear manner I should still have >94% capacity in 10 years time.🙊
January 13, 20223 yr Author That is why we need the early adopters on this thread so we don't need to extrapolate!
January 16, 20223 yr Some thing to think about. I have been using battery operated power tools since they first came out many many years ago ... since back in the days of NICD At the moment I have about 35 batteries used for site tools ... makita 18V ... Hilti 14,4/22 and 36V and a a pile of 10.8V. We talk about battery cycles ... SOC and DOD. How long do they last? Thats the big question, some of the machine batteries are older than 10 years ... not such a great run time anymore. I have lost 2 X Hilti 36V batteries and 3 X 18V makita batteries. The makita batteries are used and abused more than the Hilti batteries, in fact I was a little disappointed when they both failed in a lot less than 10 years ... it could have something to do with all the vibration form the using the hammer action all the time or just crap batteries ... I dont believe they achieved more than 500 cycles ...but Hilti didnt have the equipment to test the batteries ...they only had a device to inform me that the battery was dead and I had to fork out another R10K plus vat. The makita batteries on the other hand, only failed after 10 years and most of them are still operating. This is the part which I believe is important ... The makita machine which have a star, will shut the machine off to prevent damage caused by a low battery. The 3 batteries which have failed where all used in the blower which doesnt have a star and I inserted them into the charge straight after using the batteries which at the time were still hot from using it. ... something I don't do anymore ... I normally take the battery out of the machines when I finish using it and pop it in the charger (regardless of the time of use) ... I now put the battery on the shelf, next in line to be charged. Think about your solar setup ... if you discharge your battery fast which will result in the battery getting warm/hot ... then suddenly you switch on the charger and start pumping 100 amps back into the battery ... could it damage the battery. Most of the information I read about damaging batteries, has to do with temperature management. The last set of gel batteries, replaced under warranty ... the first question asked "do you have a temp. probe in the battery compartment?". Do you manage the temperature were your batteries are kept and do you manage the temperature when the batteries are being discharged and do you have a time delay to allow the batteries to cool before recharging ... especially if you are discharging to as low as 10 or 20 % ... is it as important as the rate of discharge and the DOD?
January 22, 20223 yr Author On 2022/01/16 at 12:51 PM, isetech said: Do you manage the temperature were your batteries are kept and do you manage the temperature when the batteries are being discharged and do you have a time delay to allow the batteries to cool before recharging ... especially if you are discharging to as low as 10 or 20 % ... is it as important as the rate of discharge and the DOD? The BMS should take care of all of this - for instance not charging at very high or low temperatures.
January 22, 20223 yr 1 hour ago, RichardZA said: The BMS should take care of all of this - for instance not charging at very high or low temperatures. Personally I view the BMS settings as operating at the extreme min and max levels for protection. I would rather manage the system as to not trigger the BMS on a daily basis because it is there.
January 22, 20223 yr Battery Brand/Model: 5x Pylontech US3000B Installation Date: 2019-02, 2019-07, 2019-09 & 2020-02 Cycles: 618, 526, 479 & 363 Performance: SOH is 96% according to ICC. I think that's the value for the oldest battery, not an average. Discharge limit is set to 25% SOC. They typically discharge to 60% SOC (summer nights) and 45% SOC (winter nights). Average temperature over the 3 years is 25.7°C (min 16°C & max 32°C). Very happy with their performance. May buy another one if La Nina returns. There's a 5th US3000B with broken comms (@#$% lightning!) that does not report it's SOC/SOH/etc. Because its BMS still works, I have connected it up to assist the other batteries. It's flying dark, but still pulls its weight. Edited January 22, 20223 yr by ChristoSnake Forgot about the 5th battery
March 15, 20223 yr Just curious as a total beginner can’t you set up a modified fridge with thermostat setting to keep the batteries at optimum temperature? easy to set up …
March 15, 20223 yr @Z100 ("What's this fridge doing in your Battery room? ...... Are there beers in? ..... No you silly, it's my batteries! ) Yes you can, but too much of a hassle. I have installed a temperature controller in my "Solar Room" which controls 4 cooling fans on the batteries. Temp setting is min 23 degrees C and max is 28. It's working like a bomb. (Designed it myself and made the circuit boards as well. Electronics is my hobby )
March 15, 20223 yr 3 hours ago, Z100 said: Just curious as a total beginner can’t you set up a modified fridge with thermostat setting to keep the batteries at optimum temperature? easy to set up … If you visit big battery rooms like those using 104 x 200Ah single cell batteries (220V DC lead acid) you will always find fans to exhaust the fumes, running water in case of a acid spill and an aircon to keep the temp low.
March 15, 20223 yr One of the better performing lifepo4 cells at lower temps, 25c is the sweet spot, others can get ugly at 0 and less I'll post a temp vs C charge/discharge rate tomorrow here, it applies to these cells only though, but its an indicator at least. Edited March 15, 20223 yr by Nitrious
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