cheap system lifepo4 battery and tv ,spotlights ,etc with solar charging.
The first thing.
The battery I made here is lithium iron phosphate (LiFePo4)
Or also called (LFP)
Chemical type with a nominal voltage of 3 per battery.
2 volts, because its charging/discharging curve is very flat under this voltage, it outputs current for a long time at about 3 volts.
2 V, it also maintains voltage stability under high discharge load, so there is no voltage depression.
When the discharge of the battery management system ends (BMS)
Decided that it had reached a low point that it did not want the cell to be below (2.
5 volts per grid)
It will turn off the battery to protect it.
Away from your knees, it is said that you will be happy!
The LFP battery can be discharged to a very low charging state, so it takes only about half of the lead-acid capacity to replace the lead-acid type.
If you have a 400 amp hour L/a battery, all you need is a 200 amp hour LFP battery to replace it.
People who consider switching tend to make mistakes when considering prices.
Another advantage of them is on board.
If you keep them cool, there is no gas to worry about, but it is important to use the 3Kw inverter and induction cooker, you can also avoid the inherent explosion and suffocation hazard of the gas LPG system.
Please note that it is not lithium ion (Li-Ion)
It\'s not LiPo, it\'s lithium iron. The complete battery has a compression edge, and the BMS and stainless steel bars are 13.
5 kilograms, 50 amps at 24 volts. See pictures.
Please note that I decided to remove the sides and bottom of the plywood to help with heat transfer, which is not what I noticed, but in the process of charging the heat is the enemy of any battery.
It boils a very small electrolyte in the plastic separator and becomes a gas that occupies ten times the volume, so that the pressure rises and the battery is affected.
Operating the charging voltage of two 250-watt batteries at 66, the monthly output of the ampere-Max-power charging mode has doubled to about 35 volts at 15 am amps.
However, the package was quickly charged in the morning.
It only takes an hour or two.
After 10 months of this phase in December 2018, there is no problem, terminal corrosion, wire corrosion or anything harmful.
I connect the inverters with two stainless steel bolts and they are as clean as a whistle.
I have removed all the details of my cells and my proposal from Mr 884216512
I was completely ignored when I tried to contact him with a failed phone.
This is the last message I gave him on April 2019, and the 21/5/19 battery, although carefully balanced the top and bottom and kept watching, only kept the rated capacity of about 40%.
Don\'t buy these cells!
My phone was flown from China. 8 cells at 3. 2V is 25. 6 nominal.
Each battery must be charged to 3.
My battery is 55 volts first.
Some manufacturers recommend higher voltages, but all of them refer to charging and balancing for the first time.
This is the so-called \"top balance \".
If you look at the chart at the point where the curve is rising rapidly, it can be seen as a good sign of battery filling.
If all your cells show 3.
2 v you don\'t know if each unit is a quarter full a, half full B, three quarters full C or almost full D!
There are several ways to do this.
What I chose was to charge each battery 3.
55 V, then connect them in parallel for one day so that they can stabilize under the same voltage pressure.
Normal about 3.
2 v by getting them all to this point, you have \"balanced\" your cells, when the current is pulled out, they should all provide similar energy off before a cell gets too low.
The same amount of energy should return to each cell when charging, and they should be full at the same time.
In practice, this seems to be quite close to life 4.
I paid $25 for a 50 amp hour battery with a rectangular ventilated aluminum box with connectors.
They are all packed in a heavy carton with a protective dense foam inside.
Only two weeks from payment date to arrival.
Plus audd300 Air Freight $250.
The service is good but the air freight is expensive.
I drew more red on the front end.
For these old eyes, it is hard to see from the factory.
There is also a simpler way to handle the connections they provide.
I made the connector as shown in the figure, because when dealing with the terminal nut, I can support one side of the connector connection so that I don\'t trigger the terminal because the relevant metal wire is damaged.
My hand is very big and clumsy.
Australia has just imposed an additional 10% GST on goods below $1000, so prices are much higher now.
Weight 1 per cell.
35 kg, this is important because there is fraud in the battery market and the weight is the only indicator you can show that the battery will be truly full.
For all lithium batteries, you need some kind of compression to prevent the anode cathode and the plastic separator from separating from each other.
Foil-type packaging is hard to do, but the rectangular packaging above is simple. Note; -
There are laying pieces on the bottom and side.
I realize now that this is a mistake.
I think I should cool the airflow on both sides.
I am updating this Instructure, like a blog, to add information and experience as I study.
This is the build video I ended up using, but the price could range from $20 to $30.
Pay very close attention to the cut off voltage as they look the same in 4.
The 2 v model will also be destroyed, and LFP batteries have purchased some cheap used 250 watt solar cells that were removed by the person who installed the rental system.
$20 each for all accessories and main switches. Ten of them .
They have a built-in blocking diode that can stop any current flow in the reverse direction and 3 bypass diodes that can help with coloring. .
Later, someone on Gumtree sold me 22 new panels and a 5000 watt grid-connected inverter for a $500 plus all the alloys and accessories, which I was surprised. (
All new and unused)
It\'s cheap to buy solar connectors from ebay and it\'s cheap to buy about 30.
Solar connectors these panels have a maximum voltage of 30 V and a maximum voltage of 8 v. 5 amps approx. (30V x 8.
5A = nearly 250 Watts enough. )
I bought a 12/24 V automatic solar charging controller for about $236.
It has a maximum power point, just lower the input voltage at the point where the maximum amps flow into the battery to match the battery voltage.
This could be dramatic, and I \'ve seen 15 am ps flow into my battery from the sun-filled two panel series.
I have attached a recent video recording the changes when charging at the Max Power Point.
PV inputs of about 60 v or more may increase.
Seeing this picture, the unit works fine and I can change the high and low points and the charging voltage to fit me and ps4.
The SMK charging controller I use. . . .
Note: I am trying to contact their email on service @ smksolar.
Com had a problem with the lithium settings and was completely ignored, so I don\'t recommend SMK anymore.
There is no built-in lithium in Algoithm, they claim to have, and these settings will continue to jump back into the lead-acid settings.
Don\'t buy their charger
Check the end of the email I sent.
I noticed that there are more products on the market now, as long as you can set the top charging voltage point, the maximum power point can actually work, and a cheaper version can do the job.
The following explanation will let you read the battery voltage based on the Arduino processor chip, build your own battery cheaply, and turn off the Arduino solar charger accurately. The old lead-acid system doesn\'t work here.
Don\'t connect the two types of batteries together as you will flatten your s4.
The solar controller will take at least 50 volts or so to work, so a single panel will not work.
I connected the two panels in series with a maximum output of 60 V and was working fine and still gave me 8 v.
5 amps Max panel.
These panels are very secure and now you can connect them in series to increase the voltage to a maximum of 1000 volts. (
The maximum power point becomes 15 Am ps around 36 V, which is the maximum power point, but it has been changing)
This shows that it is legal to connect and play up to 90 v dc voltage in Australia.
It started to get dangerous on top of that, so I didn\'t go there.
Arc welders output a DC voltage of 50 to 70 volts, which is why they can use it safely.
The higher the voltage, the lower the current, so the higher the end voltage means a thinner wire can be used.
I bought it from ebay.
It cost me a $115 and there is a plug on it that fits many different countries.
Ebay site for 24 V/240 V inverterTo connects all of this and gets wire sizes etc. This video may help beginners to connect.
There is wiring from the panel to the controller.
Wiring from the controller to batteryring from the controller to the load, in this case this is my inverter/TV and my LED safety spotlight.
Once you \'ve gone so far, you can test the inverter and the TV is working on the battery.
Wiring of BMS-
BMS only runs on the negative line.
The input is connected to the charging controller and output to the negative battery terminal.
All sensory lines must be installed on each unit as indicated.
Leaving like this, I was able to run the 170 w LCD Plasma 55 inch TV for about 10 hours, and the cut off of the inverter stopped everything because of the low voltage.
I deliberately didn\'t connect the solar panels at that time to see how long the battery would last.
I think it will run 24/7 if the solar input is enough.
Solar charging again, fast and intelligent.
A few years ago, I bought 4 20-watt LED lights for a $20 each.
They need a 24 V voltage and have the circuit reach about 32 V in the light to get the ultra-high brightness.
There are no stupid little things.
These consume about 3/4 of the AMP at a 24 volt voltage, so two people use one and a half amps from my battery.
These are 24 volt LED lights, but I can\'t find the LED lights around me.
Also, I bought a bunch of street light dark sensors for ebay AUD $4 and all I need here is one, mobile sensor for each AUD $4, here are two, I hung it under the lamp on a curved sheet of aluminum.
Light sensor 24 v ebay example mobile sensor 24 v ebay example they have to be 24 v to use this battery.
Since these are run by the battery, I have to change the motion sensor to shorten the delay time, otherwise my battery will run out a bit.
To do this successfully, I replaced a resistor with a lower value.
Look at the picture above.
I \'ve messed it up for a while, and I think I \'ve identified the final picture, removed the R14 and replaced it with a normal resistor at the bottom of the variable pan that controls the delay.
Resistance is 2. 2 KilOhms .
Seeing the discussion here, you will also find that the capacitor used in it is 25 volts.
I get in trouble from time to time and I think the hat needs to be changed to about 40 volts.
This is it.
It took a long time to perfect, but changing to lithium iron phosphate is a big advantage.
The photo above shows the foil bag I\'m trying to make, but it\'s a waste of time.
The second is a great way to see the state of the battery at a glance.
EWT life450ah 12 v review disassembly and load testing this video is worth a look as he cuts directly into it to show you what\'s going on inside these types of batteries.
About $389 per vehicle, they have 26650 round case batteries that are the same as the Tesla Mod 3 car.
EWT life450ah 24 v replacement Wiki on LFP reduces prism batteries such as display boards. Expensive BMS system, cheap PCM protection circuit module (PCM)-
The board is connected by the positive and negative of the battery and diverts the excess voltage (
Limit over IC internal selection)
As heat by resistance.
Cheap PCM and 8 s 25 amps for $41 80 amps for $67 but postage keeps me from getting the right one on Ali
Indicate up to 60 amps with all correct cut-off values.
This is currently running my system and there is only one charging/discharging port for charging and discharging records at AUD 31 60 amps.
The rowing group that uses them has 240 cheap double cup batteries here. This is a load test for something like a cylindrical battery, which is why you should observe how you work around the terminal!
This is a supplier of batteries directly to you in Australia. This is a 12 volt LED headlight that works well in the 12 volt system update in January 2019 after 6 months. No, I didn\'t use any type of additive at all on the connection.
I noticed that its capacity is falling.
It wouldn\'t run an 80 watt bulb and two safety lights all night as it used to be, so I looked into the battery while the controller was off and found that it was actually BMS turned off.
When solar comes in the morning, everything is back and the packaging is charging normally.
When testing cells at the closing point, I found that the two cells closest to the positive end were 0 lower than the other cells.
Only 30 v, but this is enough to make BMS trip in advance.
I used a 5 v LED power supply designed to run an LED light strip to charge the two batteries to match the other batteries, which seems to have fixed the problem of early shutdown.
I found a device that can tell me the status of the string at a glance.
This is a Celllog8.
It tells me that the string is almost full at 26.
89 V, that is, the maximum slot voltage is 3.
366 volts, the lowest is 3.
358 V, 8 mV between high and low cells.
There are other settings on display, but I put it there and it barely uses any current settings. They are $ ?
I will post when I find them again.
The Recorder\'s user manual is a PDF file as shown above.
Update 209i after 8 months decided to try to balance my cells at the bottom today, so I released them by running the TV until the package was cut off.
It only gave me 5 hours and 5 amps, so 25 Ah instead of 50 Ah. ! !
When I checked the voltage, I looked at the batteries and I noticed that a battery had been falling quite fast all the time, although no current was taken out while everything was disconnected. OOPS .
The unit is the take-off point of BMS.
All the electronics are coming out of this terminal. Not good .
It looks like this particular battery has some sort of self-discharge problem that doesn\'t keep its capacity and pulls the package down very early.
I have to change that cell.
I hope I will not go the same way again.
If they are filled at 8 months, then they are useless as cells.
This is the question I asked about the SMK solar controller. . . .
Service @ smksolar.
ComIn advertises this product on Ebay and you say it works for lead-acid batteries and lithium.
You also mentioned \"user settings \".
I have looked into this model in use and there is no lithium setting at all.
There is a user setting, but it also uses a volume, float, absorption, and equalization algorithm that is completely unsuitable for lithium.
I have a 24 volt lithium iron phosphate battery.
It requires a constant current charge of 20 Am ps until the battery reaches 3.
4 V/cell and then a constant voltage of 3.
4 volts/cell until the current drops below 5 amps.
There is no such setting on your product.
How can I reach this charging cycle? Thank YouQuote. . . .
The life of the aluminum package battery is twice that of the plastic package battery, and it is difficult to accurately measure the life of the lithium battery.
Therefore, we would like to elaborate on this topic to help the intended lithium user understand the issue and summarize how to get maximum life from the battery pack.
Understand charging cycle life-lithium pair
Lead Acid usually, the life of any battery is measured according to the number of times the battery is charged, and can only maintain a capacity of 80% when the battery deteriorates to the new battery.
This number is called the \"charging cycle life\" of the battery \".
As a comparison, I want to start with lead-acid batteries.
The charging cycle life of lead-acid batteries has been between 350 charges before 600 charges.
The charging cycle life typically found in car starter batteries is low, and the charging cycle life found in laboratory or solar storage applications is high.
But things may become a bit misleading.
Honest ways to measure battery life can be manipulated.
Because there is Peukert effect in all lead-acid batteries, you can\'t discharge more than 55% of the battery, the new 20-hour capacity rating.
Before it is considered to be fully discharged, the 100 amp-hour Ah lead-acid battery will only generate about 55 Ah of electricity.
Lithium batteries are not affected by Peukert\'s law, because the lead-acid battery is, so you can discharge the lithium battery to 20% of its fully charged state before the battery is considered to be discharged.
For many lithium batteries, it will not damage battery life if the discharge exceeds 80% mod, but it is generally believed that the lithium battery is fully discharged at 80% mod.
In order to conduct an honest test to determine the exact life of the lithium battery, the battery must be fully charged and then fully discharged to 80% DOD.
It takes a lot of time to charge and discharge thousands of times, so most companies charge in a few full cycles and then infer the remaining life expectancy batteries based on some known chemical reaction curves.
Disadvantages of lithium titanium battery and polymer battery lithium titanium battery has the longest life span.
However, they are 3 to 5 times more expensive than ordinary lithium iron phosphate \"life po 4\" batteries.
Lithium nickel cobalt magnesium (
Also called polymer battery)
Or the life of the NCM battery is about half the life of the lithium ion battery.
The NCM battery is lighter in weight and lower in cost, often appearing in electric vehicle applications where cost and weight are critical.
How some companies cheat on charging cycles and they say their lithium ion batteries will last for a while
For example, 8000 charging cycles
These numbers are unrealistic if they discharge the battery completely to 80% DOD, which is not realistic for them.
However, there are several other factors in the battery life scenario.
One of them is the battery situation.
They generate heat when the battery is charged or discharged.
The heat trapped inside the battery can lead to a decrease in battery life.
The life of a plastic packaged battery given Ah grade will be shorter than that of a metal packaged battery.
This is because plastic is a poor thermal conductor.
The smaller the Ah rating of the battery, the easier the battery stack will dissipate heat from the core of the stack, so the longer the life.
The honest manufacturer of the lithium phosphate plastic encapsulated battery that I call a prism battery usually claims that their battery will have more than 2000 charging cycles.
A prism-like plastic encapsulated battery is shown in the chart in this paper.
Why is the performance of lithium battery in aluminum package better? Typical aluminum encapsulated batteries have better heat dissipation and higher performance.
Depending on the battery size, the expected charger cycle life of the smaller lithium ion battery can be up to 4000 charge cycles and follow the same trajectory of the plastic prism battery as shown below.
The simple fact is that if you have an app, you want a long life, like solar storage, and you don\'t discharge the battery to a level below the nominal 3.
2 voltage you will have a battery that may live longer than you.
The discharge depth has a very far-reaching impact on the life of lithium batteries.
What is the expected life of the aluminum shell battery? -
Factor 1: discharge depth . . . . . . Percentage of capacity used per cycle. -
DOD is the abbreviation of the discharge depth, which is used to describe the depth of the discharge of the battery.
If we say a battery is full of 100%, which means that the MoD of this battery is 0%, and if we say that the battery has already delivered 30% of the energy, there is a 70% energy reserve here, we say the MoD for this battery is 30%. -
Factor 2: discharge rate, Ampere divided by capacity-
Read the chart above and here are some examples.
All the numbers are 1C discharge rate, which is positive.
At a discharge depth of 90%, your battery will provide a cycle of 2400 to 80%-of-Original-Capacity (SOIC)C.
At a discharge depth of 10% (
Engine start, for example)
Your battery will provide 35,000 cycles before 80% SOIC.
After more than 35,000 cycles, the battery is still working, but gradually loses capacity, but the performance is declining.
Conclusion: The DOD is reduced by charging the lithium ion battery more frequently (
, Increased battery cycle life.
Solar energy is usually a helpful way to reduce the MoD and increase life!
I found my cells a little too high occasionally and triggered an alarm on the Celllog8 where I monitored the cells.
I also noticed that my battery pack seems to have a lower capacity than it should be, so this time I decided to try the bottom balance.
I ran out of my battery pack until one of my automatic devices cut it off and then balanced from there.
Because one cell goes down faster than the other cells.
In my case, 5 V is enough to trigger the package through the controller.
I cut off the power on the 24 th charger with 25 v.
4 V on inverter, 20 V on BMS, alarm on celllog8 set to 24 V. 5V . . . .
So in my case, I started to be a bit high.
When I separated the cells, I found that I had 3 cells. 2 V to 2. 8 V .
I was discharged after three. 0V down to 3.
0 v, which got me into the knee of the cell discharge curve above (
Or I prefer to call it a waterfall)
Then, like the first picture, establish a connection to connect cells in parallel.
I then use the existing connector to connect the two units in parallel. .
See the second picture.
Then I connected the cut wire to the top according to 2nd pictures.
Now I can observe the current with the ammeter.
You can see the reading on the photo.
It starts with a maximum of 5 amps, goes down to 4 amps in about 5 minutes and goes down from there all the time.
I monitor the current between each pair until the current drops to 0. 005 amps (5 milliamps)
As usual, insert any wires to the maximum, then disconnect all connections and reassemble the package.
At least 48 hours.
I think it\'s worth numbering each cell to match the celllog8 number and put some tape on the BMS and celllog8 sense lines so they don\'t get confused.
In my example, I just started working from the positive red line on the BMS loom and connected each black in order, using celllog8, which has a black negative lead and then in order.
I will update while watching, but everything seems to be fine at this point.
The packaging is being recharged.