PolyQuest engineers designed the Protection Circuit Module (PCM) to greatly reduce the chance of accidents while charging lithium polymer batteries. It is critical that each cell is limited to a maximum charge voltage of 4.2 volts per cell and that only chargers approved for lithium polymer batteries are used. Since the greatest risk of fires in polymer type batteries is associated with overcharging, caused by improper charger settings, the PolyQuest PCM can eliminate this problem.

If you are not planning on using the PCM Guard, or follow the extensive Precaution and Safety tips posted on this website, we strongly recommend you do not purchase or use Lithium Polymer cells or packs.

Use of PCM is optional but highly recommended by Pure Hobby.
Most warranties aren't covered if the PCM isn't purchased and utilized.

Many great chargers have been introduced for Lithium Polymer packs to eliminate fires caused by over-voltage charging.  Smart Chargers have been manufactured with very accurate voltage sensing circuitry that detects improper charge voltage.  These type chargers will not charge a pack that doesn't match the users voltage settings of the charger.  This is a great feature to reduce the risks of fire but PolyQuest has taken it one step further by introducing the PCM Guard.

 

The downside to Smart Chargers is that they can only check to see if the total charge voltage is correct and the number of series-connected cells in the pack.  No charger can detect the state-of-charge of each cell when charging multiple cell packs.  3 cells in a pack will eventually become imbalanced due to use beyond recommended discharge rates, over-capacity discharge or due to impact damage during use.  If 2 of the cells reach 4.2 volts during charging, and the imbalanced cell is still at 4.1 volts, the charger would start to overcharge the 2 cells as it is trying to reach 12.6 volts for the 3 cell pack.  Therefore, the 2 charged cells may get damaged or even cause a fire due to cell rupture from extensive gas generating within the cells while overcharging.

 

REMEMBER,!!  Lithium Polymer cells and/or assemblies should ONLY be charged or stored within a fire-safe container.  Never leave Lithium Polymer cells and/or assemblies in temperatures that exceed 130F.

 

Why you need the PolyQuest PCM Guard

If the PCM Guard detects that any one cell in the pack exceeds the limit it will electronically disconnect the pack from the charger and the warning LED light will go out on the PCM Guard.  Although the PCM should work with any Lithium Polymer charger, we always recommend using a Smart Charger that will detect and refuse to charge if the setting on the charger do not match the voltage of the pack.  We make no guarantees that the PCM will function properly with any Lithium Polymer chargers, but if used in conjunction with a Smart Charger, the risks of fire and/or rupture is greatly reduced. The PCM, a voltage-limiting device that prevents single-cell over voltage charging, is for use only on PolyQuest Lithium Polymer packs.  PolyQuest installs a multi-connector cell tap on the packs to match  the PCM Guard.  When connected between your lithium polymer charger and the pack, the PCM Guard limits charge voltage to 4.2 volts per cell with a short-time maximum of 4.35 volts to reduce possibilities of false warning. PCM Guard is available in 3 configurations PCM Guard 2S is for use on 2S packs only PCM Guard 3S is for use on 3S packs only PCM Guard 4S is for use on 4S packs only PCM Guard Specifications Maximum Input Voltage 18 volts Maximum Charge Current 5 amps Overcharge Protection Voltage 4.35 volts +/- 0.025 volts Overcharge Protection Release Voltage 4.15 +/- 0.060 volts Dimensions (L x W x H) in (mm) 55.0 x 35.0 x 5.0

 

REMEMBER!!  Lithium Polymer should always be monitored while charging.  If you are not going to follow all the charging safety instructions, then make sure you are using a fireproof container away from flammable materials or simply don't use or purchase Lithium Polymer batteries.

 

Simply connect the proper PolyQuest PCM Guard between your charger and the PolyQuest Lithium Polymer battery pack.  In most cases, the operation will be automatic.  The red LED on the PCM Guard will be continuously lit during the charging process.  If and when any cell exceeds 4.35 volts, the LED will start blinking and the charge circuit will be disconnected automatically.  The LED will go off which would indicate cell metering/balancing needs to be performed.  PCM does not guarantee that cells will be charged evenly but will prevent cells from being overcharged causing rupture or fire.  Individual cell metering or balancing would need to be performed with the use of the Multi-Connector Cell Tap Harness if you feel there is a problem (see notes below).  PCM does not guarantee damaged cells being properly charged and we do not recommend ever using damaged cells.  If Red LED is on, you know the pack is safe.

 

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Multi-Connector Cell Tap Harness

With the Multi-Connector (factory attached) you can measure each cell individually to determine which cells are imbalanced and need attention to prevent any possible accidents.  Pure Hobby does not perform any cell balancing procedures.  These procedures require knowledge of electronic circuits and can damage equipment or cause personal injury if connections are made incorrectly.  We strongly recommend you see an Authorized Technician to perform cell balancing.  Pure Hobby  accepts NO liabilities for accidents arising from improper use or lack of product knowledge.  If you have any doubts of your ability to safely diagnose and re-balance cells then either locate someone who does or simply do not purchase and/or use Lithium Polymer batteries.  Never, and under no circumstances, should damaged cells be used. Follow the safety guidelines for discharging and disposing of the cells. The diagrams shown here are for reference to knowledgeable technicians that understand electronics circuits. Knowledge of correct procedures and connections are critical in performing cell metering and re-balancing Polymer cells.

 

Poly-Quest Lithium Polymer Batteries distributed by Pure Hobby are approved only for the Radio-Control Market.
Use in any other application is not permitted without prior approval.
Charging, discharging, use for Electric Motors and Flying Models may cause serious personal injury or property damage.
In purchasing/using Poly-Quest Polymer Batteries, the buyer/user, agrees to accept all responsibilities of these risks
and not to hold Poly-Quest (manufacturer), its Distributors or Retailers (owners and employees) responsible for
any accidents, injury to persons, or damage to property.

Since many Radio-Controlled applications exceed the manufacturer's recommended maximum discharge rates there
is no warranty (expressed or implied) by the manufacturer, its Distributors and Retailers in respect to the
Cycle Life, Capacity, Cell Characteristics or Storage of cells/packs used in the Radio-Controlled market.