Amazon.com: BXX 3200mAh V12 Battery Replacement for Dyson V12 Detect Slim, 965470-01, SV20, SV26, SV30, SV34, SV35, SV46 : Health & Household

The battery case appears similar to the one that came with my new Dyson V12 detect slim and it fits well. It is marked as 3000 mAh instead of the 3200 mAh stated in the product description. While that was more than the OEM battery’s 2500 mAh rating, it did not run any longer. In a controlled test using the smooth floor brush set to “auto”, both batteries achieved the same 33 minutes runtime before shutting off. The time remaining readout was meaningless with this battery – randomly going up and down and showing 30 minutes remaining when the battery ran out of charge. It was also difficult getting a reliable charging status. Given the unsupported readout, this battery is judged not as good as the original.

Dyson batteries for the V12 slim are perpetually out of stock so when I saw this 3rd party alternative appear on Amazon I decided to give it a try. My wife is thrilled and the battery lasts longer and does more work than the Dyson original. Only difference noted is that since it has more mah than the OEM battery the LCD display of running time remaining is inconsistent and not a good predictor of actual running time remaining.