Sur Ron 72v 42Ah “König” 500A (Burst) 3025Wh

£2,499.00 (price including VAT)

Sur Ron 72v 42Ah “König” 500A (Burst) 3025Wh

Out of stock


Sur Ron 72v 42Ah “König” 500A (Burst) 3025Wh

The Most Powerful Sur Ron Battery in The World!

High Power Long Range 3326Wh

Molicell P42A 21700 Cylindrical Cells.

Full Bluetooth BMS (battery status).

UK Warranty

Now in a Tough Protective Stainless Steel  case powder coated black !

Fully Protected by BT BMS

Only Ship To UK Mainland – Sorry No: No overseas – International shipping

Free UK Shipping

These are very special order and only made in limited numbers.

This is the most powerful battery we make for Sur Ron. Recently tested in full race conditions (Brushless Enduro at Ashdown MX August  2022)

Design especially to handle the super high power of the latest KO motor. Also ASI BAC4000 or ASI BAC8000 and Nuclear controllers  (any 72v capable controller) up to 500 Amps Peak  (phase 800A) and use on the Sur Ron Light Bee. Designed for minimal sag. Heavy duty welds and connectors using a single set of the Sur Ron standard Supra D6 and a super load carrying QS8 Ant spark (we supply the extra power lead with 6AWG cable.

These are designed and fitted on our bikes that are set over 16KW (too much for a Sur Ron motor)

This will not work with the original 60v X Controller.

The 72 42AH 500A Sur Ron Battery 20S10P 72v  3024Wh Molicell P42A 21700cell,  with ANT Bluetooth BMS (works on IOS and Android for series monitoring) designed to fit inside the Sur Ron battery compartment. Because of the extra height (370MM), lid hatch spacers wil be needed (supplied). The Cells are genuine branded cells specifically designed for high output discharge and sustained high drain. Other inferior cells used in cheaper packs simply can’t deliver like these. Th UK retail price of these cells is over £9 each!!

The whole battery is fitted in  hand made stainless steel case designed to handle those inevitable and hopefully not painful “Offs” with hard off road rides and giving masses more protection. The casing is powder coated inside and out.


We have done our best to keep the battery as low as possible. We never want to sell a battery for the Sur Ron where the lid does not close. However, you simply cant cram this amount of cells into a bike without making some minor and simple alterations. We want our batteries to be able to swap over in less than 5 minutes. When we go Enduro racing with very long laps, we want as short a paddock stop as possible if required.

To fit the this battery we removed the battery  from the bike and then removed the very basic hinges for the battery compartment. Swapped in our hinge extenders (we supply all this). It makes swapping batteries really easy (takes 30 seconds). We also supply bolts and spaces to allow the lid fastener to reach the lock.


Weight 18.2KG
Cells Molicell P42A 21700 (200).
Bluetooth ANT BMS set at 500  Amps Peak.  Full battery protection including over discharge (shorts) over heating etc
Each cell with additional individual wrapping for added protection.
Additional double layers of nikle sheet.
Heavy duty discharge cables: 8 AWG with Supra D6 Connector and 6AWG QS8 Anti Spark
Additional layers of fiber board, Kapcon tape, heat shrink with internal/external powder coated stainless steel sealed box to give maximum protection and insulation.
Double sandwich configuration using 2 x 0.2mm pure welded nickle sheet.
Bluetooth BMS giving individual series condition with balanced charging. We do not recommend altering our settings as may invalidate your warranty.
An integrated handle for lowering the battery in and out.
Charging port via an XT60 connector.
The main battery to controller connectors we use are the same type as used by Sur Ron to keep everything compatible. This allows you to swap your standard battery back should you wish.
Battery is in a super tough stainless steel case with handle, designed to keep your battery safe in an accident and waterproof except immersion or direct jet washing at the cable exits.
Supplied with handlebar volt meter.
THIS KIT DOES NOT INCLUDE A CHARGER. Chargers can be found here (10A MAX):
From our tests, not all Sur Ron frames are exactly the same. Sur Ron recently seem to have let their quality control down a bit. On our mark two prototype (pre releases) we suddenly found that our case did not fit in the 4th bike we tested it in , Sur Ron hand not cleaned the battery compartment frame welds. We then went back to the drawing board and re-designed the case.
The new and for sale case has flitted all 4 test bikes. Its a snug and tight fit to maximize the cell capacity and keep the battery as low as possible. It is very slightly possible that there is anther bike out there with poor welds. In this case there is a very  small possibility that your bike welds will need cleaning up with a dremmel/grinder, although with this latest design we have not found this in over 300 installs. This is a simple job and causes no damage to the bike. I would like to make the point clear that we do not expect this to be needed  by 99.9% of our customers the battery should slot straight in.

Please ALSO note, these are genuine new cells and made up into complete battery specially designed by us, built at our oversees  factory or here in the UK by our dedicated battery builders. We simply can’t buy a single battery, Thanks to PayPal fees, shipping and taxes (hate VAT) the markup is minimal!

When connecting the battery to the bike and to avoid a spark. Turn the red trip switch on the bike to off. Connect the older original power cable and then turn the red trip to on. Then connect the new power leads. Removing battery has no special order.

Charging: First time charging is VERY important. Always connect the charger to the battery with the charger powered up from the mains. This will stop a “Connection Spark”. The battery needs a “Balance Charge” on first charge. Please charge for 12 hours first time.

Please note, Lithium batteries are considered hazardous and due care and attention should be taken. Although these cells are in wide use, and professionally manufactured in a purpose built factory; because of the power of the battery, we strongly recommend that precautions are taken. We do not recommend charging inside the family home and charging should be supervised. We take no responsibility for misuse. These batteries are thoroughly tested (full discharge and charge cycles at the manufacturing stage and also pre-delivery). These are not DIY or amateur built devices.

Please note, charger is not supplied but can be found here:+

* Warranty, due to the nature of use of these devices  (off road) warranty is limited to 6 months from date of purchase. Any damage the result of water ingress, alteration, may void warranty. This includes shortening of cables and changing connectors. It is the owners responsibility to proof against water ingress and not use in unacceptable very wet conditions, or use direct water from hose/washers. Any alteration modification to this controller or its subsequent wiring, even cutting the power leads to make shorter will immediately invalidate any warranty. Even battery disconnected, the controller can still maintains current and can be shorted/damaged. The controllers are waterproof, but can still suffer from water damage through the connector and hence are not covered for water damage. Controllers are not covered by warranty after 14 days.
Using high PAS in a high gear under heavy load may cause the controller to overheat (power level 9 in a small rear cog). Gears should be used going uphill or any other heavy load.
Attempting to reprogram the controller may cause damage.
Warranties are not transferable.
We reserve the right to slightly modify or change this product without notice.

** Bike not included


Buyer releases Electron Cycles or any person trading on or behalf of the business known as Electron Cycles from any liabilities, therein known as Electron Cycles (expressed or implied, arising by law or otherwise) that may occur from the use of products sold by Electron Cycles and purchased by Buyer. These products are being sold for “Off Road/Competition Use” only and may be used only on two wheel vehicles (bicycles, electric bicycles, two wheel electric powered vehicles) used solely for “Off Road/Competition” (off-road being defined as a private land with land owners permission and not public highway or byway). The Buyer also recognises that Lithium batteries are classed as hazardous and should not be: stored, used, charged in place, facility any area that is not fire proof or safe to do so. That batteries should not be taken into the family home, office, workplace or school place. No other applications are intended or implied. The Buyer of product sold or provided by Electron Cycles acknowledges and agrees that Seller disclaims any warranty and expressly disclaims any liability for personal injury or damages or any damages to vehicle, expensed occurred, personal property or third persons. Electron Cycles will uphold the warranty of the manufacture of the product sold for a period of six months from date of purchase from manufacturer defect. In the event a manufacturer’s warranty exists, it is agreed and stated that Under no circumstances shall the seller or manufacture be liable for any labour charged or travel time incurred in diagnosis for defects, removal, or reinstallation of this product, or any contingent expenses.







Additional information

Weight 19.99 kg
Dimensions 50 × 30 × 25 cm