hi guys, the battery i use for my steam blower is the maplin 12V 1.3Ah SLAOrder Code: MM22Y and as you can see in the pic, it will fit this loco with room to spare. it can keep the blower running all afternoon so should run this loco for long enough. it does not say gel battery on the website, but i have been told thats what they are. they do them in different output powers, mine is the lowest at 1.3. the dimensions are on the spec page and i was told NOT to charge them from a car batt charger so i got the maplin one 12V Sealed Lead Acid Battery Charger 350mAProduct Code: LL30H. luckily i have a maplins in town so can peruse. also, they have increased in price since i bought mine about 4 yrs ago. i used one of these batts in a gauge1 hymek to pull six coaches no problem. would certainly buy again. found some nice dark green paint so may use that now i have finished sticking more bits of card all over it. ....martin