MS621FE-FL11E
| Part Number | MS621FE-FL11E |
|---|---|
| Manufacturer | Seiko Instruments (SII) |
| Category | Battery Products > Recharging Batteries (Secondary) > Coin Cell / Button Cell Batteries |
| Description | Rechargeable MS (Manganese Silicon) Lithium Coin Cell Battery, 3V, 5.5mAh, SMT Tabbed Terminal Assembly (FL11E). |
| Stock Status | In Stock |
| Origin | Original Factory |
Product Overview
The MS621FE‑FL11E is Seiko’s 3V rechargeable MS lithium coin cell with factory‑fitted FL11E SMT solder tabs. Rated 5.5mAh @2.0V cut‑off, it delivers >100 deep cycles and >1000 shallow cycles for RTC, memory backup, wearables and IoT devices. Manual tab soldering only; reflow oven assembly is strictly forbidden.
Core Advantages
Long Cycle Life & Good Overcharge Resistance
Seiko MS chemistry supports repeated charge‑discharge and tolerates continuous trickle‑charge without fast capacity drop.
Stable 3.0V Output
Consistent 3.0V platform, directly compatible with 3V IC, RTC and low‑power MCU.
Factory FL11E Solder Tabs
Pre‑attached FL11E terminals for manual PCB soldering. Reflow soldering prohibited.
Wide Temperature & Low Self‑Discharge
Reliable ‑20℃~+60℃ operating range with low self‑discharge for long‑term standby.
UL1642 Safety Certified
Meets UL1642 lithium‑cell safety standard for consumer & industrial electronics.
Key Specifications
| Brand | Seiko Instruments (SII) |
|---|---|
| RoHS Status | RoHS Compliant / EU Directive Compliant |
| Warranty | 1‑Year Standard Quality Warranty |
| Package / Case | Coin Cell Φ6.8mm; Body thickness 2.1mm, total overall height 2.2mm including FL11E SMT solder tabs |
| Mounting Type | Manual tab soldering, NOT suitable for reflow oven |
| Surface Marking / Silkscreen | MS621 / SII Logo,Marking |
| Battery Chemistry | Rechargeable Lithium Manganese Silicon (MS) |
| Nominal Voltage | 3.0 V |
| Nominal Capacity | 5.5 mAh (Discharged down to 2.0V cut‑off) |
| Standard Charge Voltage | 3.1 V to 3.3 V (Recommended 3.1 V ± 0.15 V) |
| Max Charge Current | 0.5 mA (current‑limit resistor required) |
| Continuous Discharge Current | 0.015 mA (15 µA) Standard |
| Max Continuous Discharge Current | 0.25 mA |
| Cycle Life Performance | 100 cycles (100% DOD), > 1000 cycles (10% DOD shallow discharge) |
| Operating Temperature Range | -20°C to +60°C |
| Storage Condition | 10℃ ~ 30℃, Relative Humidity ≤60%RH |
| Safety Standard | UL1642 Compliant |
| Dimensions (Body Only) | Diameter: 6.8 mm | Height: 2.1 mm |
| Overall Height (With Tabs) | 2.2 mm (use for mechanical enclosure design) |
| Packaging Format | Tape & Reel / Tray Packaging |
Precautions
- Charging Voltage Limit: Do not exceed 3.3V. Use a current‑limiting resistor to avoid over‑pressure, leakage or cell damage. Max charging current: 0.5mA.
- No Direct Body Soldering: Only solder FL11E tabs. Do not heat the battery body. Soldering condition: ≤350℃, ≤5 seconds. Reflow soldering is forbidden.
- Prevent Short‑Circuit: Avoid positive‑negative short‑circuit; high surge current will permanently damage the battery.
- Correct Polarity: Confirm PCB polarity before soldering. Reverse charging will destroy the device.
- Storage Requirement: Store at 10‑30℃, humidity ≤60%RH. Keep away from high‑temperature and humid environment.
- Disposal: Dispose waste battery per local environmental regulations.
Typical Applications
- Real‑Time Clock (RTC) power backup in smart meters, security systems, and industrial controllers
- SRAM and non‑volatile memory data retention in IoT sensors and industrial electronics
- Wearable medical monitoring devices, digital cameras, and handheld terminals
- Backup power for wireless communications modules, GPS trackers, and smart beacons
- Portable consumer electronics, solar‑assisted devices, and embedded system power modules
Order & Shipping Info
| Minimum Order Quantity (MOQ) | 1 Piece |
|---|---|
| Shipping Time | Shipped within 1‑2 business days |
| Delivery Time | 3‑7 working days worldwide |
| Shipping Methods | DHL, UPS, FedEx, EMS, YFH Standard |
| Payment Methods | T/T (Bank Transfer), PayPal, Credit Card, Western Union |
Technical Support
For datasheet, sample requests, stock check, bulk pricing and custom versions with solder tabs, pins and wire assemblies, please use the Quick Inquiry form. We will reply within 24 hours.
Frequently Asked Questions
Q1: Is the MS621FE‑FL11E primary(non‑rechargeable) or secondary(rechargeable) battery?
A1: It is a rechargeable 3.0V MS‑type lithium coin cell, designed for repeated charge‑discharge backup applications.
Q2: What does the “FL11E” suffix in part number stand for?
A2: FL11E is Seiko solder‑tab code, defining tab geometry and welding position. Different FL‑series suffixes change footprint; direct swap needs PCB modification.
Q3: What charging circuit is required for MS621FE‑FL11E?
A3: Charging range:3.1‑3.3V, max charge current limited to 0.5mA. Hardware must add series current‑limiting resistor.
Q4: Can I get custom terminal tabs or wire‑harness assemblies?
A4: Yes, custom solder‑tabs, pin‑out and wire assembly are available. Send quick inquiry for custom battery solutions.
Q5: What is the difference between MS621FE and MS621FE‑FL11E?
A5: MS621FE is bare coin‑cell without tabs; MS621FE‑FL11E comes with pre‑welded FL11E tabs. All electrical specs are identical. You may use bare MS621FE if you weld tabs yourself.
Q6: Can I replace MS621FE‑FL11E with CR‑series primary button cell like CR2032?
A6: Not recommended. CR‑series are non‑rechargeable primary cells. MS621FE‑FL11E is rechargeable secondary cell with charging circuit. Mix‑use may cause swelling, leakage and safety risk.
Q7: Can I use MS621FE‑FL11E for reflow oven SMT production?
A7: Absolutely no. It cannot sustain high‑temperature reflow profile. Only manual soldering on FL11E tabs allowed, ≤350℃ within 5 seconds maximum.
Q8: What cross‑brand compatible alternatives exist for MS621FE‑FL11E?
A8: Limited drop‑in equivalents are available. Some competitors share similar voltage and capacity, but chemistry, cycle‑life and dimension may differ. Verify specs before replacement; direct swap is not guaranteed.
Q9: Why body thickness is 2.1mm but total height reaches 2.2mm?
A9: 2.1mm is pure cell body thickness. 2.2mm is overall height including raised FL11E metal tabs. Adopt 2.2mm value for housing and mechanical clearance design.



