Battery Cell Monitor & Balancer - coming soon
Battery Cell Monitor & Balancer
(with prototype enclosure)
The Battery Cell Monitor & Balancer is a precision instrument that ensures that multi-cell batteries are maintained in an optimal state, improving system reliability and prolonging battery life.
The Battery Cell Monitor & Balancer does exactly as its name suggests: it monitors cells within a battery, and it balances those cells if and when they require it. The Battery Cell Monitor & Balancer can be used in two ways:
- As a programmable hand-held battery verification tool, or
- Installed in a UAV, either with or without interfacing to the vehicle's CAN bus.
Interfacing with a vehicle's CAN bus provides real-time access to individual cell voltages and battery temperature (with the addition of a suitable external sensor). Control of balancing is also possible via commands sent over the CAN bus.
The Battery Cell Monitor & Balancer plugs directly into the balance connector present on most Lithium-based batteries. In many cases, this is the only connection required. A pair of indicator lights on the front panel show the battery's state of charge and state of balance.
Features:
- Supports multiple battery chemistries - LiPo, LiS and LiFe.
- Supports 4S, 5S and 6S cell configurations.
- DC-isolated CAN interface, allowing stacking (for series connected batteries).
- Battery temperature monitoring with suitable external sensor.
- User-friendly configuration software.
- Rich variety of balancing control options.
- Seamless integration with 250W PMU and 1700W GCU.
- Weight: 45g (1.6oz).
- Dimensions: 80.0 x 35.0 x 11.5mm
Why is cell balancing important?
Unlike lead-acid batteries which require little maintenance and are very forgiving of neglect, Lithium-based batteries require care and vigilence if reliability and long-life are to be realised. In a worst-case scenario, a poorly maintained Lithium battery can spontaneously catch fire if given sufficient provocation.
As a Lithium battery is charged and discharged repeatedly over time, its cells will begin to diverge in their state of charge. This occurs even though the charging and discharging currents for all cells are identical.
If a battery is charged up to its nominal fully-charged terminal voltage, some cells will be overcharged and some will be undercharged. Overcharging damages cells and reduces the battery's lifetime, and undercharging means that the battery is not storing as much energy as it is capable of. More catastrophically, overcharging damaged cells is a risk factor for spontaneous ignition.
In summary, cell balancing:
- Maximises the energy stored,
- Increases battery life, and
- Reduces the risk of fire.
Purchasing:
Available soon from Millswood Engineering.
Product resources
- Documentation:
- Product brief: a short summary of the key features and specifications.
- CAN protocol: describes what values the Battery Balancer can measure and transmit, what commands it can receive, and how this data is formatted.
- Software:
- Configuration utility: a Windows app for configuring the Battery Balancer and checking that it is all working correctly.
More resources are available here.