Lithium Battery 12V/180Ah (LFMP12V180AH)
A large capacity 12V battery consisting of 4 cells. A simple solution for a variety of the 12V applications. Ideal for an energy supply in off-grid installations, boats, caravans, etc. It is a completely preinstalled battery.
The initial charge: The battery must be charged to full and each cell needs to be balanced before using.
Download the specification file: GWL-LFMP12V180Ah.pdf
This is a special time-limited offer.
The specification for the 12V LP models of the LiFePO4 batteries
Check the updated version of the specification for the 12V block models of the LP batteries. Download the PDF file here.
FAQ: What is the charging voltage of the 12V battery? 16V or 14.4V?
Question: Some web pages and the GWL blog says that the final voltage of the charge for 12 LP battery is 16V. But some other pages and some charger specifications give information about charging to 14.4 ~ 14.6V. What is the difference?
Answer: The maximal charge voltage for the LiFePO4 technology is 4.00 per cells (16.00V per battery). This is the recommended charge voltage for the initial charging to balance all the cells to the same full level. Check the explanation here.
However for the long term use it may be better not to charger to full, but to charge to a lower voltage to get the maximal life-span. For example charging to 3.65V per cell is considered to be around 85% charge. It works very well for 1000, 2000, 3000 and more cycles. That is why some of the chargers (example the TC-Charger models) charge only to 3.65 V per cell (14.6V per battery). See the additional information at this post.
LP 12V/20A – customer reference – 530 cycles
I am using LiFePO4 batteries for 1.5 year in a cyclic use. The energy drop after 530 cycles is in average about 2 percent. The batteries have always had higher capacity than given by the manufacturer. At this time they still have higher capacity than the nominal value - in average 110%. I am using 12V/20Ah batteries. I have altogether 50 batteries. The weakest of them still has 21 Ah of useable energy. To get ideal performance, it is best to keep the voltage of each cell in between 3.0 to 3.5V. When voltage is dropping bellow 2.8V the battery may become misbalanced and the cells may be damaged.
Solar charging test data - October 2011
We are using two 217Wp panels to charge a 48V pack of 3x 12V90AH batteries. Download the results of the total energy collected - XLS file. Check the detailed results of the LOG files. The data are recorded using the PowerLog 6S device and processed by the http://www.logview.info/ software. You can download the complete data logs here - ZIP file.
Harvesting the power of the sun
We have set up a new configuration to test the solar charging of LFP batteries. Two solar panels (217Wp each) are in a serial string to charge a 48V/90Ah battery pack made of 4 pcs of LP12V 90AH batteries.
During a sunny day in October, we are able to gain more than 2 kWh of energy from the 2 panels. (38Ah at 53V = 2kWh)
Our tests have a multiple purpose: to test the solar charging, to examine different solar controllers, to study the charging of the LFP batteries and finally to make a working solution to disconnect from the grid for ever.
If you are interested in these solutions, keep checking our blog or contact us directly.
I want to replace the lead acid 12V 100Ah stating battery. Which LFP model can I use?
Answer: The performance of the LFP batteries concerning the starting current is excelling the performance of the SLA (lead-acid) batteries. Our tests and the tests of our customers show that the LP12V 40Ah battery can replace any SLA starting battery (even the 100AH, or 150 Ah models). Even big diesel machines can be started from the LFP battery at very cold weather.
For long term use and massive deployment, we suggest to make testing for each application to make sure that the replacement LFP battery will work properly for long time.
FAQ: What is the real experience with LiFePO4 batteries?
Answer: The Winston Battery (formerly Thunder Sky) has been producing the LiFePO4 batteries since 2004. The first large volume customers were from the USA. These American customers have been using the LFP batteries from some 5 ~ 6 years with full satisfaction. (Even though there were some problems with the quality of the cells from some of the early production batches.) It is important to note that over the years the technology has been developing. The new LiFeYPO4 technology is much more stable and production quality also continues to grow.
FAQ: I purchased a new LP 12V battery. Why is the battery different from the model I purchased several years ago?
Answer: The original Thunder Sky 12V LP batteries used to have electrochemical balancing (with a floating electrolyte). There were produced from 2007 till spring of 2009. Later versions contained individual cells with mechanical separation. The production of the original LP batteries was stopped in 2009. The news models (40Ah, 60Ah, 90Ah) are produced using individual single cells that are selected in the factory to match the performance and capacity.
FAQ: Can I charge multiple 12V batteries in series at the same time with one charger? (i.e. 2 batteries for 24V, 3 batteries for 36V, etc…)
Answer: Yes, it is possible to charge a battery pack consisting of multiple 12V batteries in series at the same time using one charger. However following needs to be observed:
1) The initial charge – you need to charge all the 12V batteries individually to full voltage level BEFORE you start using them together as a pack.
2) We strongly recommend to use some kind of management to make sure all the batteries are working within the proper operating voltage levels. For example the Akumon may be used to monitor the status of the batteries.
Additionally we remind the need to observe the general instructions concerning the use of the 12V batteries.
FAQ: Battery deeply discharged – what to do?
By mistake I have deeply discharged the 12V LP battery. When I discover this situation, the voltage of the battery is < 4 Volts. How can I restore the battery?
Honestly, there is no way to restore the LP/LFP cells and batteries if there were deeply discharged. (Bellow 2.5V per cell or 10V per 12V battery.) If the battery is deeply discharged the internal structure of the cells is damaged. There is no way to get the battery back. The battery must be replaced with another battery.
Trying to charge this kind of empty battery will only result in even bigger damage and the battery will swell and release the gases! Never try to “correct” the problem by swift charging!
The only option is to disconnect the battery and wait for some time (hours/days) to see if the voltage returns back to the minimal level. If the voltage returns by itself, there is still hope that such battery may be charged. However this charging must be done with very small currents (0.1C or less) and the charging must be monitored. If the voltage does not return and stays low, the battery is dead.
FAQ: “Sudden” battery discharge
I have bought a several of LFP cells and made the pack with them to replace the lead-acid battery in my houseboat. The LFP battery was working great and it gives much more capacity than the lead acid. However after several weeks of usage, I came back after the weekend and I found out that the battery is completely discharged. Why this happen?
Please note that unlike the lead acid batteries, the LFP batteries will be completely damaged if you discharge them bellow the minimal voltage (usually >2.5V per cell, or bellow 10V for 12V battery). This may happen if you have some equipment that takes the power from the battery continually. Maybe you simply forget some light or some equipment „on“, and after few days the battery is deeply discharged and damaged forever.
The example: 12V 90AH battery is connected to houseboat with alarm. This alarm takes only 5W of power (12V 0.4A). If the battery has 70% charge, the alarm will discharge the battery in about 150 hours, that is 6 days. If you have some equipment with higher power consumption, the discharge will be much faster, even perhaps less than one day.
In order to prevent this kind of „mistaken“ discharge, we strongly suggest to monitor the battery (or the cells) to see the voltage of the pack. We also suggest using the protection devices to give warning when the battery is getting low. Also when leaving for a longer period of time, please be sure to disconnect the battery from the load completely with some mechanical switch or circuit breaker.
The suggested equipment: the CellLog to monitor the voltage (and give the alarm), BM1 – battery monitor, or the Akumon - 12V LFP battery management board.
Concerning the “self-discharge”: due to the chemistry of the LFP cells, the internal discharge of the cells is very low, less then 3% in a month. The LFP cells are internally very stable and it would be a very unusual situation if the cell would discharge by itself in some way. It is virtually impossible that several cells in one battery would discharge at the same time. The reality shows that majority of these “discharge” failures are due to the negligence of the battery user.
If the LFP cells or the battery were deeply discharged, there is no way to restore them back to proper function.
You must charge before the first use!
We remind all users of the LFP cells and LP batteries that the cells and batteries MUST be charged to full voltage level BEFORE assembling into a pack and before starting to be used.
For the 3.2V cells, the full charge voltage level is 4.00V and the charging is described here. For the 12V LP batteries the full charge voltage level is 16.00V. More details about the use of 12V batteries is here. (Check also the section about the 12V LP batteries)
Even in simple installations, it is important to make the first charging. Example: when assembling a 48V pack using 4 pieces of 12V batteries, it is very important to charge all batteries to the same voltage (16V) before assembling the whole pack. Only after the batteries have been balanced to the same voltage level, it is possible use them as a pack and to charge the whole pack together using the 48V charger.
Please remember: FIRST CHARGE, THEN USE!
Simple solar solution for off-grid applications
This is our demonstration panel for simple solar solutions based on the 12V LP batteries. Check with us if you need such solutions.
Testing Solar-charge controllers with LP batteries
Sample 1: STECA SOLARIX MPPT 2010
This is a Maximum Power Point Tracking (MPPT) solar charge controller. It works perfectly. It gets the maximal power from the solar panel. The ideal peak reached was 200W of power input from 217Wp solar panel. The average solar input was 130W to 150W (from 217Wp panel during a sunny day in Prague, Czech).
Sample 2: PHOCOS CIS20
This is a Pulse-width modulation (PWM) solar charge controller. This controller will limit solar panel output voltage according to the battery voltage. It is not suitable to be used with the high voltage FV panels (e.g. our 217Wp panel with max 36V). It is designed to be used with the so called “12V” solar panels.
The ideal peak reached was 140W of power input from 217Wp solar panel. The average solar input was 80W to 90W (from 217Wp panel during a sunny day in Prague, Czech).
You can download the test data results from the links bellow:
http://www.auto88.cz/_info/Tests/STECA-SOLARIX-MPPT-2010-1.pdf
http://www.auto88.cz/_info/Tests/STECA-SOLARIX-MPPT-2010-2.pdf
http://www.auto88.cz/_info/Tests/STECA-SOLARIX-MPPT-2010-3.pdf
http://www.auto88.cz/_info/Tests/PHOCOS-CIS20-1.pdf
http://www.auto88.cz/_info/Tests/PHOCOS-CIS20-2.pdf
http://www.auto88.cz/_info/Tests/PHOCOS-CIS20-3.pdf
Concerning the LFP batteries
The usage of the 12V LP (or LFP) batteries is completely trouble-free. Both regulators do not exceed 14V on the battery charge voltage output, so the 12V LP battery will never be overcharged.
Be sure to contact us for more details on the use of the LP batteries with the solar controllers.
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