Youmile 5 pcs 18650 Lithium Li-ion Battery Charger Board 3.7V 4.2V to 5V/9V 1A DC-DC Step Up Boost Module Adjustable charge and discharge + 5 pcs 18650 battery box

Very useful little chip. -: If you battery already has protection circuitry make sure to solder the two pads on the back together to bypass this chips protection circuitry...

Voltage adjustment work and the charging is also OK.

All 5 turned out to be rubbish 3 out of 5 didn't work out the packed absolute rip off

Super Teile! Ersetzen einen Stromwandler (z.B. Step-Up converter) + Ladeelektronik für einen Li-Ion-Akku + USB-C Stecker und sind sehr kompakt. Werden etwas Warm beim laden des Akkus, bisher aber ohne Fehlfuktion. Eignen sich gut um kleine mobile Geräte zu bauen, z.B. ein beleuchtetes Türschild o.Ä..

Fonctionne parfaitement, charge de la batterie, et sortie step-up ajustable jusqu'à 27v.

Very good combination of charger and boost-converter. I use one for powering a DSO150 hand held oscilloscope

18650生バッテリー用と書くべき 保護基板のついた物は長さが合わず使えない 生バッテリーは発火のリスクが高く使用すべきではない

Ad ora ho utilizzato solo una schedina delle cinque, funziona correttamente, ci sono due led indicano correttamente lo stato della ricarica, ma per una batteria da 2200 mA ha impiegato quasi 3 ore. Non ho rilevato eccessivo riscaldamento. L'ho scelta per la presenza dello step up, un pò di creatività per fissarla ad un supporto.