18650 3S8P 11.1V 20.8Ah Li-ion Battery Pack 20800mAh High Capacity for Power Station AGV E-mobility Backup UPS Industrial Equipment | Custom OEM | CE In Stock

🔋 18650 3S8P Battery Pack — 11.1V 20800mAh 20.8Ah Large Capacity Li-ion Pack

Overview

This 18650 3S8P lithium-ion battery pack connects 24 Grade A 18650 cells in a 3-series 8-parallel configuration, delivering 11.1V / 20800mAh (230.9Wh) — the largest standard 3S cylindrical pack configuration in our lineup. Engineered for portable power stations, industrial robots, heavy-duty AGV systems, medical mobile stations, and large-format UPS backup, it provides exceptional multi-hour runtime at stable 11.1V. Integrated smart BMS with 24-cell balancing, CE and UN38.3 certified, full OEM customization available.

3S8P Architecture

┌──────────────────────────────────────────────────────┐
│ String 1: [A1]──[A2]──[A3]  =  11.1V / 2600mAh      │
│ String 2: [B1]──[B2]──[B3]  =  11.1V / 2600mAh      │
│ String 3: [C1]──[C2]──[C3]  =  11.1V / 2600mAh      │
│ String 4: [D1]──[D2]──[D3]  =  11.1V / 2600mAh      │
│ String 5: [E1]──[E2]──[E3]  =  11.1V / 2600mAh      │
│ String 6: [F1]──[F2]──[F3]  =  11.1V / 2600mAh      │
│ String 7: [G1]──[G2]──[G3]  =  11.1V / 2600mAh      │
│ String 8: [H1]──[H2]──[H3]  =  11.1V / 2600mAh      │
│                   ↓ Parallel ↓                        │
│        Total: 11.1V / 20800mAh = 230.9Wh             │
│               24 cells total                          │
└──────────────────────────────────────────────────────┘

3S = 3.7V × 3  = 11.1V        ← system voltage
8P = 2600mAh × 8 = 20800mAh   ← total capacity

Key Specifications

Full Voltage Reference

3S Full Series — Capacity Ladder

⭐ 3S8P = Maximum capacity in the standard 3S 18650 format. Stepping up further requires switching to 4S (14.8V) or larger cell format (21700).

3S8P vs 3S7P — Upgrade Justification

📌 When to choose 3S8P over 3S7P: When runtime is the top priority and the 150g weight increase is acceptable — particularly in stationary or cart-mounted applications where weight is not a constraint.

Multi-Cell Capacity Options — 3S8P

⭐ Default: 2600mAh Grade A — best cycle life, cost, and stability ratio.

Runtime Estimation

📌 Based on 230.9Wh at 85% system efficiency.

⚠️ Voltage Application Guide

BMS Protection — 24-Cell System

Applications

🚢 Shipping & Compliance

🚢 At 230.9Wh, this pack exceeds the IATA 160Wh air freight limit. Sea freight is strongly recommended. We provide complete UN38.3 certification, MSDS, and DG packaging guidance for all maritime shipments.

Charging Guide

⚠️ Requires dedicated 12.6V / 3S balance charger rated at ≥15A output. High-current charger mandatory for this pack size.

Default Package Configuration

OEM / Custom Options

Certification & Compliance

Why Choose Us?

• 🏭 Factory Direct — own large-format pack assembly, zero intermediaries
• 🔋 230Wh large pack expertise — 24-cell matching and BMS tuning is our specialty
• ⚖️ 24-cell grade matching — cells selected within ±10mAh tolerance per string
• 📐 Full 3S ladder — 3S2P to 3S8P from same factory, one supplier
• 🚢 Sea freight specialists — complete DG documentation for >160Wh packs
• 📋 CE + UN38.3 standard — all docs included
• 🔬 10-day OEM sample — large pack prototyping in-house
• 🛠️ End-to-end OEM — cell selection to certified mass production

📩 Need maximum 11.1V runtime? Share your device power draw and duty cycle — we’ll confirm whether 3S8P or a custom configuration best meets your spec.