MS621T-FL11E
| Part Number | MS621T-FL11E |
|---|---|
| Manufacturer | Seiko Instruments (SII) |
| Category | Batteries & Power Products > Rechargeable Batteries (Secondary Cells) – Coin / Button Cell |
| Description | Rechargeable Manganese Silicon Lithium (MS) Coin Cell Battery with Tab Terminals, 3.0V Nominal Voltage, 3.0mAh Capacity, Compact 621 Package, Operating Temperature Range (-20°C to +60°C). |
| Stock Status | In Stock |
| Origin | Original Factory |
Product Overview
The MS621T-FL11E is a compact rechargeable Manganese Silicon Lithium (MS) coin cell from Seiko Instruments (SII). Equipped with factory pre-welded FL11E solder tabs for PCB mounting, this 3.0V battery delivers stable performance for power backup. With a miniature 621 size (6.8 mm × 2.1 mm) and operating temperature of -20°C ~ +60°C, it is ideal for RTC, SRAM memory backup, IoT equipment and automotive telematics.
Core Advantages
Advanced MS Battery Chemistry
Adopts manganese silicon lithium material, featuring low internal resistance, stable voltage and reliable discharge performance.
621 Small Form Factor with FL11E Tabs
Pre-welded FL11E terminals support PCB installation; avoid direct soldering on battery shell to prevent heat damage.
Excellent Overcharge Resistance & Cycle Performance
Adaptable to continuous trickle charging, stable capacity and long service life for long-term backup scenarios.
Low Self-Discharge & Anti-Leakage Design
Seiko sealed structure reduces self-discharge, guaranteeing long-term backup power storage.
Key Specifications
| Brand | Seiko Instruments (SII) |
|---|---|
| RoHS Status | RoHS Compliant / Lead-Free / Green |
| Warranty | 1-Year Standard Quality Warranty |
| Package / Case | Coin Cell 621 (6.8 mm Diameter × 2.1 mm Height) |
| Mounting Type | PCB Solder Tab Mount (FL11E Lead Frame Terminal Configuration) |
| Surface Marking / Silkscreen | SII MS621T Marking |
| Battery Chemistry | Rechargeable Manganese Silicon Lithium (MS) |
| Nominal Voltage | 3.0 V |
| Charging Voltage | 2.8V to 3.3V (Standard 3.1V to 3.2V) |
| Nominal Capacity | 3.0 mAh |
| Standard Discharge Current | 0.015 mA |
| Maximum Continuous Discharge Current | 0.15 mA |
| Internal Resistance | Approx. 60 Ω |
| Cycle Life | ≥100 cycles (100% Depth of Discharge) |
| Operating Temperature Range | -20°C to +60°C |
| Weight | Approx. 0.23 g |
| Packaging Format | Tape & Reel / Tray / Bulk |
| Installation Notice | Cannot pass reflow soldering, only manual soldering on tabs |
Precautions
- Charging Voltage Control: Keep charging voltage between 2.8V ~ 3.3V (recommended 3.1V – 3.2V). Voltage exceeding 3.4V will damage the cell and shorten service life.
- Soldering Requirements: Never solder directly on the battery casing. Soldering is only allowed on FL11E tab terminals to avoid thermal damage.
- Current Limiting Suggestion: Add a series current-limiting resistor on the charging circuit to avoid large surge current after deep discharge.
- Polarity Check: Confirm positive and negative polarity before installation; reverse charging will destroy the battery.
- Usage Restrictions: Do not expose the battery above 85°C, deform, disassemble or discard it into fire.
Typical Applications
- Real-Time Clock (RTC) and SRAM memory retention in ultra-compact smart utility meters and gateways
- Automotive telematics, keyless entry fobs, eCall emergency positioning modules, and dashcams
- Smart home IoT sensors, security alarm devices, and Bluetooth Low Energy (BLE) beacon tags
- Miniature medical diagnostics, wearable health monitors, and portable testing instruments
- Point-of-Sale (POS) terminals, electronic shelf labels (ESL), and compact digital devices
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: What does “FL11E” mean in model MS621T-FL11E?
A1: FL11E stands for factory pre-welded lead frame terminal layout, specially designed for SMT and through-hole PCB assembly.
Q2: What benefits does Seiko MS chemistry bring compared with common rechargeable coin batteries?
A2: It delivers stable output voltage, low internal resistance, good overcharge tolerance and outstanding capacity retention under long-term trickle charging.
Q3: Can MS621T-FL11E be used with 3.3V main power circuits?
A3: Yes. Its nominal voltage is 3.0V. It can be continuously float-charged at 3.1V~3.2V with a simple resistor-diode circuit on regulated 3.3V power rails.
Q4: Are there alternative or compatible battery models?
A4: MS621T (without tabs) is the bare coin cell equivalent. If you require different terminal styles, customized FL series tabs can be requested. CR621 non-rechargeable batteries cannot be used as direct replacements.
Q5: Can I use reflow oven to solder this battery?
A5: No. Reflow soldering is forbidden. Only manual soldering on FL11E metal tabs is allowed; never solder directly onto the battery shell.
Q6: What is the proper charging voltage range for MS621T-FL11E?
A6: Recommended charging range is 2.8V ~ 3.3V, ideal float voltage 3.1V ~ 3.2V. Voltage over 3.4V will damage the cell permanently.
Q7: What typical scenarios is this battery suitable for?
A7: Mainly for RTC clock, SRAM data backup, smart meters, wearable devices, asset trackers and low-power IoT modules requiring long-time standby power supply.


