Free Delivery
Free Delivery
Free Delivery
Free Delivery
Free Delivery
AK 20 Battery
SKU: Stihl | LI-4520 400 6535
- 36V, 4.0Ah, 144Wh lithium-ion
- CONSTANT POWER output
- 4-LED charge indicator
- Cold start feature to -20°C
- Regular price
- £96.75 Ex VAT
- £116.10 Inc VAT
- RRP: £107.50 Ex VAT
- Sale price
- £96.75 £96.75 Ex VAT
- Regular price
-
- £116.10 £116.10 Inc VAT
- Was £107.50 Ex VAT
Free Delivery Over £75 *
Worldwide Shipping from the UK
Trusted UK Arborist Retailer
30-Day Easy Returns
Product information & specifications
STIHL AK 20 Battery — 36V 144Wh Lithium-Ion
The STIHL AK 20 is a powerful 36V lithium-ion battery for tools in the STIHL AK System. With 4.0Ah capacity, 144Wh energy and a weight of 1.2kg, it offers a strong balance of runtime, handling and performance for homeowners maintaining gardens, lawns, hedges and outdoor spaces.
It's in stock at Gustharts as an authorised STIHL dealer, with free UK delivery on this order.
Compatibility note: the AK 20 delivers full power with most AK System tools, but runs at reduced power with the MSA 70 chainsaw and REA 60 PLUS pressure washer, and cannot be used with the MSA 80 chainsaw.
Built with STIHL intelligent battery management, the AK 20 delivers CONSTANT POWER output so compatible tools maintain consistent performance as the battery discharges. Four LED indicators clearly show remaining charge, and a cold start feature protects the cells by warming them in a controlled way, allowing operation down to -20°C.
Key Features & Benefits
- 36V, 4.0Ah, 144Wh lithium-ion battery for AK System tools
- Lightweight at 1.2kg
- Integrated 4-LED charge indicator
- CONSTANT POWER output for consistent tool performance
- Intelligent battery management system
- Cold start feature for operation down to -20°C
- Compatible with AL 101, AL 301 and AL 501 chargers
Technical Details
Why Choose the STIHL AK 20?
STIHL is one of the world's leading outdoor power tool brands, and the AK 20 sits in the middle of the AK System battery range — more runtime than the entry-level AK 10, without the size and cost of the AK 30. It's a solid default choice for most domestic AK System tools, provided your specific tool isn't on the reduced-power or incompatible list above.
Pairs Well With
Complete your setup with a compatible STIHL AL charger, or browse the full range of STIHL AK System tools.
Also Known As
Also searched for as: STIHL AK20 battery, STIHL AK System battery, 36V STIHL battery, AK20 144Wh.
FAQs
Which tools is the AK 20 compatible with?
Most tools in the STIHL AK System range at full power, with reduced power on the MSA 70 chainsaw and REA 60 PLUS pressure washer, and no compatibility with the MSA 80 chainsaw.
Which chargers work with the AK 20?
STIHL AL 101, AL 301 and AL 501 chargers.
Can it be used in cold weather?
Yes — a cold start feature warms the cells in a controlled way, allowing operation down to -20°C.
How do I check the remaining charge?
Four integrated LED indicators show the current charge level.
How does the AK 20 compare to the AK 10 and AK 30?
The AK 20 sits between them — more capacity and runtime than the AK 10, less than the AK 30, at a lighter weight.
Battery Specifications
STIHL AK 20 Battery — 36V 144Wh Lithium-Ion
The STIHL AK 20 is a powerful 36V lithium-ion battery for tools in the STIHL AK System. With 4.0Ah capacity, 144Wh energy and a weight of 1.2kg, it offers a strong balance of runtime, handling and performance for homeowners maintaining gardens, lawns, hedges and outdoor spaces.
It's in stock at Gustharts as an authorised STIHL dealer, with free UK delivery on this order.
Compatibility note: the AK 20 delivers full power with most AK System tools, but runs at reduced power with the MSA 70 chainsaw and REA 60 PLUS pressure washer, and cannot be used with the MSA 80 chainsaw.
Built with STIHL intelligent battery management, the AK 20 delivers CONSTANT POWER output so compatible tools maintain consistent performance as the battery discharges. Four LED indicators clearly show remaining charge, and a cold start feature protects the cells by warming them in a controlled way, allowing operation down to -20°C.
Key Features & Benefits
- 36V, 4.0Ah, 144Wh lithium-ion battery for AK System tools
- Lightweight at 1.2kg
- Integrated 4-LED charge indicator
- CONSTANT POWER output for consistent tool performance
- Intelligent battery management system
- Cold start feature for operation down to -20°C
- Compatible with AL 101, AL 301 and AL 501 chargers
Technical Details
Why Choose the STIHL AK 20?
STIHL is one of the world's leading outdoor power tool brands, and the AK 20 sits in the middle of the AK System battery range — more runtime than the entry-level AK 10, without the size and cost of the AK 30. It's a solid default choice for most domestic AK System tools, provided your specific tool isn't on the reduced-power or incompatible list above.
Pairs Well With
Complete your setup with a compatible STIHL AL charger, or browse the full range of STIHL AK System tools.
Also Known As
Also searched for as: STIHL AK20 battery, STIHL AK System battery, 36V STIHL battery, AK20 144Wh.
FAQs
Which tools is the AK 20 compatible with?
Most tools in the STIHL AK System range at full power, with reduced power on the MSA 70 chainsaw and REA 60 PLUS pressure washer, and no compatibility with the MSA 80 chainsaw.
Which chargers work with the AK 20?
STIHL AL 101, AL 301 and AL 501 chargers.
Can it be used in cold weather?
Yes — a cold start feature warms the cells in a controlled way, allowing operation down to -20°C.
How do I check the remaining charge?
Four integrated LED indicators show the current charge level.
How does the AK 20 compare to the AK 10 and AK 30?
The AK 20 sits between them — more capacity and runtime than the AK 10, less than the AK 30, at a lighter weight.
Battery Specifications
Delivery & Returns
UK Delivery
Fast, reliable delivery from our UK warehouse.
- FREE UK Standard Delivery
applies to eligible UK orders over £75 ex VAT.
Estimated delivery: 2–4 working days
- UK Standard Delivery from £3.60 + VAT
Estimated delivery: 2–4 working days
- Next Working Day Delivery – £6.00 + VAT
Order before 3:00pm (Monday–Friday) for next working day delivery
All UK orders are dispatched Monday–Friday and sent via a tracked courier service.
International Delivery
We ship worldwide from the UK.
- Europe from £10.00
Estimated delivery: 2–7 working days - Rest of the World from £12.00
Estimated delivery: 2–11 working days
Shipping costs and delivery times are calculated at checkout based on destination and order contents.
Customs, Duties & Taxes
International orders may be subject to local import duties, taxes, or customs charges.
When UPS is selected at checkout, applicable duties and taxes are included in the total price. For other shipping services, duties and taxes may be charged separately on delivery and are the responsibility of the recipient.
Customs processing times may affect delivery estimates.
Returns
30-Day Return Policy
- Items can be returned within 30 days of delivery
- Products must be unused and in original condition
- Return postage costs apply unless the item is faulty or incorrect
For full details, please visit our Shipping & Returns page.
UK Delivery
Fast, reliable delivery from our UK warehouse.
- FREE UK Standard Delivery
applies to eligible UK orders over £75 ex VAT.
Estimated delivery: 2–4 working days
- UK Standard Delivery from £3.60 + VAT
Estimated delivery: 2–4 working days
- Next Working Day Delivery – £6.00 + VAT
Order before 3:00pm (Monday–Friday) for next working day delivery
All UK orders are dispatched Monday–Friday and sent via a tracked courier service.
International Delivery
We ship worldwide from the UK.
- Europe from £10.00
Estimated delivery: 2–7 working days - Rest of the World from £12.00
Estimated delivery: 2–11 working days
Shipping costs and delivery times are calculated at checkout based on destination and order contents.
Customs, Duties & Taxes
International orders may be subject to local import duties, taxes, or customs charges.
When UPS is selected at checkout, applicable duties and taxes are included in the total price. For other shipping services, duties and taxes may be charged separately on delivery and are the responsibility of the recipient.
Customs processing times may affect delivery estimates.
Returns
30-Day Return Policy
- Items can be returned within 30 days of delivery
- Products must be unused and in original condition
- Return postage costs apply unless the item is faulty or incorrect
For full details, please visit our Shipping & Returns page.
