INR21700-50GB — 21700 lithium-ion cell

About the Samsung SDI INR21700-50GB 21700 Li-ion Cell 4,900 mAh 9.8 A

The INR21700-50GB is Samsung SDI's safety-oriented take on the 5 Ah 21700. Electrically it sits close to the 50E - 4,900 mAh minimum standard capacity, 9.8 A continuous discharge — but the mechanical design is different: Samsung widened the top venting area to roughly 44 mm2 against about 25 mm2 on the 50E2, thickened the can side wall from 0.22 mm to 0.25 mm, and added a bottom vent.

Why pack builders specify it

• Top vent area roughly 44 mm2 versus about 25 mm2 on the 50E2, so gas leaves faster when internal pressure rises
• Additional bottom vent gives a second pressure-release path; pack holders and busbars must not block either vent
• 0.25 mm can wall instead of 0.22 mm for better resistance to vibration, impact and assembly compression
• Keeps the 5 Ah class capacity and 9.8 A rating, so pack energy figures carry over from a 50E design

Typical applications

• E-bike and e-scooter packs – 13S4P gives a 48 V nominal pack of about 1.0 kWh; the reinforced can suits road vibration
• AGV, AMR and warehouse robots – Cells sit close together in sealed enclosures, where vent direction and propagation behaviour matter
• Distributed and residential ESS – Energy cell for wall-mounted and rack modules where discharge stays near 1 C
• Solar lighting and off-grid poles – Capacity per cell reduces cell count for a given overnight runtime target

Where it fits

Pick the 50GB for new mobility and robotics designs where cell-level safety margin and thermal propagation strategy carry weight. Stay on the 50E if the platform is already validated around it or if the 1.5 g per cell matters. Neither is a high-drain cell — both stop at 9.8 A continuous, so anything pulling sustained current above that needs the 50S or 40T instead.

Charging and pack integration

Charge CC-CV to 4.2 V within the current limits listed above and stop discharge at 2.5 V. These are unprotected industrial cells: a BMS or protection circuit is required, interconnects must be resistance or laser welded rather than soldered, and cells of different model, batch or state of charge must not be mixed in one pack. Charging below 0 °C is not permitted unless the pack implements a low-temperature charge strategy.

Certifications and documentation

UN38.3, MSDS, IEC 62133-2, UL 1642, CE, RoHS, REACH, PSE, KC, BIS, CB. UN38.3 test summary, MSDS and the cell specification are available on request.

Specification basis: Official Samsung SDI spec.