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04. Sep 2009
 
LiFePO4 discharge test at 20°C

LiFeYPO4 battery discharge characteristics under normal temperature (20°C).


27.May 2019
 
Latest articles

    16.Apr 2019
     
    GWL Battery Abuse Test Station – Sneak peek

    Blog EVPower
    GWL/Power team is carrying out the LFP cell abuse tests. We have constructed the Battery Abuse Test Station that consists of following main parts: 1) Equipment table – the measuring equipment is installed here 2) Mechanical abuse location – a block of concrete to be used as a placing area to perform the mechanical abuse 3) Fire chamber – the test chamber for short circuit, overcharge other tests 4) Exhaust fumes piping – the fumes circulate in the pipes until the sediments from the fumes settle down in the horizontal pipe – they are used to analyze the health risks associated with the abuse tests If you wish to know the results of our tests, follow us here or on our , or pages where the results will be published soon...
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    15.Apr 2019
     
    Old battery backup system in the cinema

    Blog EVPower
    What an old treasure we've found in a small local cinema: a very very old battery backup system consisting of perhaps NiFe (or NiCd or lead-acid?) cells and wall charger (switch box). Cinema's technical equipment (projector and the emergency lights) was based on DC safe voltage so it could be easily backed up from batteries. In the old days, they knew how important is to back up the key infrastructure. But nowadays, you won't find such a thing in the modern high tech 3D cinemas, letting alone the sewage plants, or many of the gas stations...

    04.Apr 2019
     
    Sneek peek: GWL/Modular battery packs

    The demonstration installation of the GWL/Modular packs which are now being developed by our technicians as a follow-up product line of our new CPM (Cell Performance Monitor: to be introduced in May 2019!). The goal of the GWL/Modular solution is to offer components and accessories that allow for simple and fully modular architecture. Simply said: the GWL/Modular project will make the life of the DC solution providers simpler and easier. We'll keep you informed.

    16.Mar 2019
     
    Raspberry Pi BMS communication module

    Blog EVPower
    Do you need to know how much capacity remains in your battery? Stay tuned - during Q3/2019 we will announce a communication module based on Raspberry Pi project. Together with our CPM1 board, it will bring you information about SoC and DoD of any battery pack from 4 to 16 LiFePO4 cells. It will allow reading this information via touch screen or TCP/IP (ethernet). On the photo, you can see LCD display connected to the popular Arduino platform. However, after the first quick tests, we found out that better performance will ensure a Raspberry Pi platform. Our team will work hard and publish some updates soon.

    07.Mar 2019
     
    Micro Energy Storage Setup – 2019 update

    Blog EVPower
    Micro Energy Storage Setup NOTE: this is a grid-tied system setup with an energy back up to the batteries. This system is grid-tied only. The micro-inverter works only when the grid is present. If the grid is down, the system does not work. It is NOT an off-grid system. NOTE (2019 update): the illustrational picture shows a system we made in 2013 with some components which are no longer available (like the 36V regulator). We've nevertheless updated the list of components below so you can make the same system with components which are up to date and available in our e-shop. * * * * * A practical realization of a small size energy storage solution with 3.2 kWh of energy capacity with 230V/230W AC grid-tied power output. The basic concept of energy storage with easy expansion. The purpose of the installation is to store the energy in the batteries and release the energy slowly when needed. Components description of the complete setup
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    04.Mar 2019
     
    Winston cells passed the China Army military safety tests

    Blog EVPower
    The photo shows the punch-through simulating a shooting from 45 mm calibre anti-tank gun. Fully charged cells are punched through simulating the shoot-through from a military weapon. The purpose of the test is to see the safety and stability of the lithium cells. As visible from the photo, the cells remained complete, did not burn, did not set on fire and did not explode. This kind of extreme abuse proved that superiority of the Winston Battery lithium cells. These cells are suitable for all kinds of applications including the heavy duty and military grade installations.

    28.Feb 2019
     
    What is the Peukert’s Exponent for LiFePO4 cells?

    Blog EVPower
    The is used for the lead-acid batteries. Simply said this exponent is the ratio between the charging and discharging of a battery. It means how much energy you need to charge compared to the energy you get when discharging. For the LiFePO4 cells, the efficiency of the charge and discharge rate is very high – above 97% and more. That is why the Peukert’s Exponent is close to 1.00. The battery producers do not give this value because it is not necessary for the LiFePO4 cells. You can find that consider using the value between 1.01 to 1.03 for different models of the LiFePO4 cells. If you need additional support, don't hesitate to ask the for help. We will always try to find the best solution for you.
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    28.Feb 2019
     
    Q&A: BMS123 Auto replacement parts

    Blog EVPower
    Question: I have the old version of BMS123 Auto and I need a replacement board. Can you help me? Answer: Yes! The solution is simple. The OUT and IN boards of the BMS123 Smart are backwards compatible with the previous version of BMS123 Auto. For the OUT-board you can just use the BMS123smart cell board without modifications. For the IN-board, you need to make a small hardware modification of the BMS123smart cell board. You just simply cut a piece of the PCB foil. Next to the (-) minus sign on the cell board, there are two golden dots. You need to cut the connection between these two dots. You can scratch the foil by means of a sharp knife or a screwdriver. If you need any additional assistance with the or Auto, please let us know. The is here for you.
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    20.Jan 2019
     
    How to calculate the cost of stored energy in a LiFePO4 cell?

    Blog EVPower
    Lead Acid or LiFePO4? This is the price per kWh stored and cycle life comparison. The two following graphs will show you the comparison between the Lead Acid and LiFePO4 batteries. The first one compares the average number of cycles (cycle life) according to the battery type and a depth of discharge. The second graph applies these figures to calculate the cost for one kWh of energy stored – again according to the battery type and the depth of discharge. If you wonder how we got these figures or even would like to calculate the costs for a kWh stored for your own battery storage system, follow the steps below the graphs. How did we get these numbers? Plus some basic terms definitions > A 300Ah battery costs around 330€ > It has a voltage of 3.2V. The battery capacity in kWh is then:3.2 * 300 = 960 Wh = 0.96 kWh ~ 1 kWh > Because we want to gain the longest possible battery durability, we will use it only for 50% of the capacity (this is so-called 50% DoD – depth of discharge). The usable battery capacity is therefore 0.5 kWh.
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    20.Jul 2018
     
    Sailing Yacht with a 12V/200AH battery bank

    Blog EVPower
    A reference project for a battery bank on a sailing yacht using the 4x WB-LFP200AH cells for the board battery and the BMS123 Smart. The battery pack is charged from the on-board AC/DC charger (35 Amp) and the generator (up to 80 Amp).
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