Well chaps, I tried hanging the battery off the back of the trolley but it seems a bit precarious to me and it pulls the plate down a bit so that when I put the powerpack back on it falls off! So I've knocked up a battery carrier out of a flat bit of thin stainless or plated steel I had knocking about (part of a cheapo barbecue set I think).
I also thought about hanging it off the front but it puts the weight high and at one end (bit like a heavy top-box on a motorbike - horrible)
Tools - hacksaw, drill, screws, handsaw, mole grips or pliers.
Flat plate with edges folded up about an inch to snugly fit the base of the battery.
50mm x 38mm wood screwed to each other side by side (100mm) x whatever the backplate is to the axle (about 10" on my trolley) so a clump of wood about 38mm deep x 10" long that fits snugly between the bottom rails, the axle and the back plate.
The flat plate of stainless steel is screwed to the wood so that when it is dropped in the bottom of the trolley the wood fits down between the rails etc and the flat plate rests across the top of the galvanised bottom rails thus supporting the battery.
As the battery has a handle that folds over the terminals making the top flat I can put a barrel on top which then sits proud by the height of the battery plus the flat plate (but not the wood which is down between the bottom rails) upon which it sits.
The leisure battery is heavy at 16kg but less the powerpack @ 5kg = 11kg extra, so like having an extra half barrel of water in weight. It is noticable but I think my trolley has the reinforced axle.
All a bit Heath Robinson but seems solid enough so we'll see how it works next week when my electrical connector arrives from Peter Fogwill.
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