The STIHL® AK 20 is a versatile, mid‑capacity lithium‑ion battery designed for STIHL® AK System battery‑powered tools. Offering a strong balance of runtime, weight, and performance, this battery is well suited for homeowners and professionals handling medium‑duty trimming, cutting, and cleanup tasks.

Key Features

• 36V lithium‑ion battery delivers consistent power throughout the discharge cycle
• Increased capacity compared to entry‑level AK batteries for longer run times
• Lightweight, compact design maintains excellent tool balance
• LED charge indicator displays remaining battery capacity
• Designed to deliver full power until depleted
• Durable construction supports long service life
• Compatible with STIHL® AK System chargers
• Ideal for use with AK System hedge trimmers, blowers, trimmers, and chainsaws

(Model number 4520‑400‑6536)

Why It’s a Smart Pick

The STIHL® AK 20 is a smart pick for users who want extended runtime without significantly increasing weight. Its balanced capacity and broad tool compatibility make it an excellent everyday battery for maintaining residential and light commercial properties.

Description:

The redesigned AK 20 battery features increased performance over the previous model and runs at full power over the entire battery run time. Easy-to-read LED display lights indicate battery charge. Compact and lightweight, this battery provides optimal power and performance for your STIHL® AK System tools with minimal loss of charge during storage. Ideal for select STIHL® AK System tools, the AK 20 battery provides optimal run times for the STIHL® MSA 120 C-B, STIHL® FSA 60 R, STIHL® HLA 56, STIHL® HTA 50, STIHL® BGA 57, and STIHL® SHA 56.

Specifications:

• Weight: 2.7 lbs
• Battery System: AK System
• Battery Capacity: 4.0 Ah
• Rated Voltage: 36 V