Comparison · Chargers

U2 or BlitzWolf BW-S4

Two models side by side: measurements taken by the author in their reviews, and their conclusions. The better value in each row is highlighted.

In brief: Based on review measurements: Test current: BlitzWolf BW-S4 (10 A vs. 2.3).

Model	U2Vapcell · 2022Read review →	BlitzWolf BW-S42017Read review →
Current, A	2	10
Test current, A	2.3	10
Review conclusion	With reservations	Recommended

Only in one review: Voltage 5 V (BlitzWolf BW-S4); Under load 5.04 V (BlitzWolf BW-S4); Ripple 200 mV (BlitzWolf BW-S4); Efficiency 89 % (BlitzWolf BW-S4); Protection 2.9 A (BlitzWolf BW-S4); Price 13.39 $ (U2).

U2: Supports four battery types and charging up to 2 A, but has current spikes and may overcharge LiFePO4 after a power interruption.

BlitzWolf BW-S4: It delivers the rated 10 A efficiently without overheating; the author liked it, though ripple is somewhat high.

Figures were taken from the review text and checked against the quoted passages. Measurement conditions differ between reviews, so read the reviews yourself before buying. Prices at the time of review.