5.5 A NEEY 4S Capacitor Balancer Board
EK-C4S5A · 3S – 4S
Whole-pack simultaneous balancing for 3S–4S packs, no external supply and no configuration. 55 g on the board.
$51.15
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Capacitor Balancer Board
NEEY 3S Capacitor Balancer Board
EK-C3S5A · also sold as Shop code 5.5A-3S
Whole-pack simultaneous balancing for 3S packs, no external supply and no configuration. 45 g on the board.
$49.00USD Unit price · shipped worldwide, duty excluded
- Every cell transfers energy at the same time rather than one pair at a time
- Patented capacitor architecture (ZL 2019 1 1259513.3)
- Runs 24/7 on the pack’s own energy — no wiring to a power supply
- Conformal coated before shipping
- Cascade two boards for packs beyond 21S
EK-C3S5A specifications
| Model | EK-C3S5A |
|---|---|
| Supported cell counts | 3S |
| Peak balance current | 5.5 A |
| Balance method | Capacitor charge-carrier, whole-pack simultaneous active balancing (Patent ZL 2019 1 1259513.3) |
| Balance current vs delta | ≈1 A at 0.08 V delta; current is proportional to delta-voltage |
| Balancing accuracy | 5 mV (typical) |
| Battery types | NCM / LiFePO4 (factory default) · LTO via solder jumper |
| Cell voltage range | NCM/LiFePO4 2.7 V – 4.2 V · LTO 1.8 V – 4.2 V |
| Pack capacity range | 30 Ah – 300 Ah |
| External power supply | Not required — runs on the pack’s own energy |
| Undervoltage sleep | NCM/LiFePO4 below 2.7 V · LTO below 1.8 V (monitored on B1) |
| Start-up threshold | NCM/LiFePO4 2.835 V · LTO 1.89 V (monitored on B1) |
| Standby current | 9 mA |
| Sleep current | 0.1 mA |
| Cascading | Supported — one or more shared energy-exchange nodes |
| On/off control | Automatic when connected to a pack; optional external switch on the marked pads |
| Indicator LED | On = balancing · off = undervoltage sleep |
| Terminals | VH3.96 mm, 18 AWG, 40 cm lead, 3 cm strip |
| Mounting | Ø3.2 mm screw holes · conformal-coated before shipping |
| PCB / finish | FR-4, 4 layers, 2.0 oz copper, lead-free HASL |
| Dimensions | L66 × W35 × T16 mm |
| Weight | 45 g |
| Operating temperature | -20 °C to +60 °C |
| Compliance | EU RoHS (Pb/Cd/Hg/Cr6+/PBBs/PBDEs within limits) |
| Warranty | 1 year |
Documentation
Included in the box
- · EK-C3S5A balancing board
- · Cell sampling leads / wiring set
- · Mounting hardware (Ø3.2 mm)
Need a different connector, lead length or silkscreen? Custom configurations are standard — send us your pack details.
Shipping & warranty
- · Free worldwide shipping — the price shown is delivered, carrier chosen for your address
- · 1-year warranty on all boards
- · EU, US and Brazil overseas warehouses for distributor orders
- · Air, sea and express routes available; CE / FCC / RoHS documents supplied with shipment
- · OEM and ODM: custom cell counts, branding and firmware configuration
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5.5 A NEEY 6S Capacitor Balancer Board
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