Reader's battery questions answered
Red Scholefield [email protected]
Professional engineer Peter F. Richiuso, P.E., wrote:
“I prevailed on one of my colleagues in the analytical chemistry lab to analyze the gas in a puffed LiPo I had. It turns out that the gas is methane (CH4). I was surprised at first, but after reviewing the LiPo chemistry and discussing it with the chemist (Ph.D., in fact) it is very logical.
“One of the electrodes in a LiPo cell is lithium oxide infused in a graphite matrix (carbon). The hydrogen for the methane comes from moisture in the air when the batteries are assembled. Lithium metal will react with water to produce lithium oxide and hydrogen. The graphite matrix supplies the carbon that combines with the hydrogen to form the methane. There's a limit to how low the humidity can be maintained since the materials used can be hazardous if they're very dry.
“Hard charging or discharging of LiPos causes heat to be generated, which accelerates the production of methane, although the methane can form even if the battery is not being used due to self-discharge.
“The result of all this is that it should be okay to use a puffed battery as long as the battery has retained most of its capacity. The amount of methane generated is rather small and once all of the internal moisture is converted, no further gas generation will take place.”
Cellpro PowerLab 6
I received the new FMA Cellpro PowerLab 6 Multi-Chemistry 1000-watt Battery Workstation for review. Upon opening the box, I was greeted with this notice on the inside cover:
“At Revolectrix we’re just as concerned about the environment as our customers are. The manual for this product is available at: www.revolectrix.com.”
All 83 pages are in English (as are all of FMA’s product-user guides). Considering that most people ignore manuals until they get frustrated poking buttons or have lost the manual by the time they discover they need to read it, making the manual available online seems like a good idea. A bonus for those considering this charger is that you can study its operational features before making the decision.
The PL6 comes with an EC5 connector on the #10 AWG input power cable. To connect to your power source — whether it is a battery or DC power supply — you will need some means to link to the EC5 connector on the power cable. Male 5 mm bullet connectors will do the job, or you can order the optional plier-clip assembly.
The plier clips are large, rated at 60 amps. Because I am set up for banana plugs on all my charging equipment, I used the best gold-plated, high-current banana plugs I could find and replaced the clips.
Before you can use the PL6 you also must get the proper adapters for the balance leads on the packs being used. The FMA Direct website (listed in "SOURCES") has a listing for specific battery compatibility. The company offers interfaces for nearly any battery you might encounter.
The adapters shown have the parallel socket for daisy-chaining for parallel charging. Power connection is through normal banana plug sockets. You will also need the FUIM3 PC USB interface cable to connect to your computer. The battery power lead uses standard banana plugs.
Information on the website states: this 1000-watt battery workstation will charge, discharge, monitor, or multiple-cycle any current or future battery chemistry.
The PL6 is built on the PowerLab 8 technology, with programming similar to the Cellpro Multi-4 (if you have used one of those). It is geared toward the power user, but is simple to operate, affordable, and meets a wide range of battery needs.
To discuss in length the extensive list of features and capabilities of the PL6 would take up far more space than I have in this column. The PL6, in combination with the charge-control software downloadable from the FMA website, offers virtually unlimited access to charging parameters. With Windows, it’s easy to alter as many as 100 settings for any of the 25 user presets, gain access to 50 additional library presets in the unit, or tap into the PC library.
Major features include advanced power management to help you set up and use existing DC power supplies or your lead-acid battery, faster individual cell IR readout, and support for safe parallel adapters (PL6 and PL8 share the same adapters), which enable charging/discharging multiple packs simultaneously by piggybacking the adapter modules.
It also features an expansion-channel mode for turning multiple PL6s into one workstation with interlocking units, and regenerative discharge that will dump battery discharges into your source battery. You can set input power supply levels to protect your source from overload.
Although a computer connection is unnecessary to use the PL6, it makes the operating parameters easier. One benefit is the ability to plot the individual cell voltage, pack voltage, current, capacity, and power-supply voltage and current. You can also control the PL6 directly from your computer keyboard.
I don't recommend charging batteries on carpeting. I do all charger evaluations and testing on my metal file cabinet and the system is never left unattended.
The default setting for plotting curves is a black background with white grid lines, x-y axis numbers, and selectable colors for the individual cell voltages. Printing the chart with a black background uses a lot of printer ink. Switch the background to white before printing, and make sure you change the text on the x-y axis to something other than white.
As with other FMA charge systems, software updates can be downloaded to your PL6 to keep it current.
Specifications
- Battery types:
- LiPo (1s to 6s balanced, 1s to 2s unbalanced)
- Lithium ion (1s to 6s balanced, 1s to 2s unbalanced)
- Lithium manganese (1s to 6s balanced, 1s to 2s unbalanced)
- A123 or lithium iron phosphate [LiFePO4] (1s to 6s balanced, 1s to 8s unbalanced)
- Ni-Cd (1s to 19s)
- NiMH (1s to 19s)
- 6 volt, 12 volt, 24-volt lead-acid batteries (flooded, gel)
- Pack capacity: 20 to 360 mAh
- Input voltage: 10 to 32 volts direct current (VDC), reverse-to-polarity protected
- Input current: 1 to 40 amps, software limited
- Power conversion: Synchronous DC/DC converter
- Output battery charge current: Adjustable range 10 mA to 40 amps, limited by 40-amp input current
- Battery discharge current:
- Internal discharge 10 mA to 8 amps, 50-watt maximum
- Regenerative discharge 10 mA to 40 amps, 1000-watt maximum
- Continuous maximum output power: 408 watts at +12 VDC input, 1000 watts at +30 VDC
- LCD: two-line, 16-character, light gray/blue backlit
- Size: 5.70 x 5.57 x 3.40 inches
- Price: $164.95 (necessary adapters can be purchased individually or in bundles)
Laptop Battery Balancing
Are laptop batteries balanced? This is something I have always wondered. My five-year-old laptop battery finally gave up the ghost, so I opened it up to see if or how balancing was accomplished.
The pack was a 2P3S configuration, giving a nominal 11.1 volts with lithium‑ion cells. There was plenty of circuitry with connections to each of the two cells wired in parallel.
Alternative Covering Material
Fellow club member Jim Hales has found that 3 mil laminating material makes a tough and inexpensive covering. Your local laminating shop often throws out ends of rolls. Ask them to save some for you.
One side of the laminate has heat-activated adhesive. Jim is a vintage model fan, as you can see by his electric-powered Esquire model.
Flying Season
Flying season is here for most of you. Make sure you give those packs that have been resting during the winter a couple of cycles to make sure they don't let you down.
Contact Me
That's all for this month. I enjoy your communications. No email access? Then drop me a note at:
The Battery Clinic 12219 NW 9th Ln. Newberry, FL 32669
SOURCES
- FMA Direct (Cellpro PowerLab 6) (301) 829-5533
- www.usastore.revolectrix.com/Products_2/CellproChargers_2
Transcribed from original scans by AI. Minor OCR errors may remain.
