36V 20.5Ah Downtube E-Bike Battery
Description
36V 20.5Ah Downtube E-Bike Battery – Lithium Battery Pack for Electric Bike Conversion Kits
The 36V 20.5Ah downtube battery is the longest-range choice in the 36V line, suited to riders who want to cover long distances with a low-to-medium power system. The 20.5Ah capacity (about 738Wh) is available as an option on the MTX 250W and 500W kits, ideal for daily commuting and extended urban use.
The downtube design is made for mounting on the horizontal or diagonal tube of the frame, giving a compact, integrated look. The battery locks onto a mounting plate with a key lock system, which gives it extra protection against theft and stability during use.
36V 20.5Ah Downtube Battery Technical Specifications
Electrical Parameters
Dimensions and Construction
Display and Connectivity
Why the 10S configuration matters for 36V systems
The 10S configuration means 10 cells connected in series, each contributing about 3.6–4.2V to the total pack voltage. 36V is the standard for low-power conversion kits (250-500W), and the large 20.5Ah capacity makes up for the lower voltage with generous range for this class.
BMS and cell protection
The battery has a 20A BMS, in a 10S7P configuration, which monitors in real time the voltage of each cell, the temperature and the operating current, preventing overcharge, excessive discharge and imbalance between cells. The casing is IP65 certified, protecting against light rain and splashes in normal use.
Which Kits It Is Optional On
MTX kits of 250W and 500W
The longest range in the 36V line, ideal for daily commuting and extended urban routes.
Light Conversions
Compatible with low-power systems, for riders who put range first without raising the system voltage.
First eBike Conversion
A light, affordable format, ideal for those who want to try an eBike conversion without a major investment.
Installation, Maintenance and Safety
Mounting Steps
- Check that the Polly DP6 plate lines up correctly with the space in the diagonal tube
- Slide the battery onto the plate until the key lock mechanism engages firmly
- Connect the XT60 connector without forcing it, observing the polarity
- Test the throttle briefly before setting off, with the level LEDs visible
Maintenance
- With 20.5Ah, the battery handles more frequent cycles without degrading as quickly as the smaller variants
- For storage longer than 3 weeks, leave the battery at 40–60% capacity, protected from damp
- A full charge takes around 4–6 hours, depending on how discharged it was
- Do not expose the battery to frost below 0°C or excessive heat above 40°C over the long term
The longest range in the 36V line
With 738 Wh and 65–85 km estimated, the 36V 20.5Ah is the highest-energy 36V battery. The page links it to the 250W and 500W kits.
- 48V 17.5Ah downtube – the next step up in voltage, 840 Wh and 60–80 km estimated
- all downtube batteries – the full range for mounting on the diagonal tube
Frequently Asked Questions About the 36V 20.5Ah Downtube Battery
What range does a 36V 20.5Ah battery give?
Why choose 36V instead of 48V?
How long does a full charge take?
Does the battery have anti-theft protection?
Details
Recommended products
What customers are saying
Va multumim pentru review si pentru aprecieri! Ne bucuram ca bateria 36V 20.5Ah a fost exact ce aveati nevoie si ca montajul a decurs usor. Va dorim drumuri placute si va stam la dispozitie oricand aveti nevoie!