The home-made battery cage

Today I continued on work from where I left off last time I did some welding. I’d been ill a few times in the intervening period which hasn’t helped with construction speed but seeing as my original completion goal had been January of 2015, I’m not that worried.

The day started with a bit of welding. I put the fourth side on the battery base and then got myself a doughnut and a cup of coffee. I’d had to wait til midday to start on account of how cold it is these days. The working day in winter is pretty short!

As can be seen. The battery fits perfectly. The base is built to be slightly bigger than the actual battery in order to facilitate easy removal and installation. There is no bottom to the center of the base in order to facilitate drainage and because the battery should be strong enough without support in the middle, given that the battery weighs but 20LBs. If the battery fails then I’ll just get a UL1 sized LiOn battery instead. All I need do is to adjust the parameters on my charge controller for lithium batteries to work well.

The next stage was to build the top - this is the piece that will bolt to the underside of the ribs. There happen to be two sets of open channel close together behind the back wheels. This is an area where the battery is liable to be bounced a bit so I’ll build it and hope it all works. If not then I can move it forward though I’m not keen on doing welding in front of the wheels. I have nightmares about things dropping off even though it’s unlikely. Too many people have put doubts into my own head about my own skills. Heck, I bet if I mentioned I drive school busses that they’d find some reason why I shouldn’t drive them or why I’m bad at it or can’t cope with the problems of driving challenging busses.

As an aside in the past two weeks I’ve driven 7 different busses each with its own issues. Two had very sensitive brakes that had two modes - full on or none. One had a steering wheel with 8 inches of slop in it. One had a maximum speed of 44mph or 1mph slower than is permitted on the interstate yet that bus had to use the interstate so I was the slowest vehicle around. One had very vague brakes that needed the pedal to the floor before they’d really work. Another had so little power that acelleration was very gradual. Think in terms of 60 seconds to get from zero to 45mph. Then there’re the different types of bus - type B, type C and type D. My normal bus is a type B but I drive anything I’m given. Oh yes and one had a terrible turning circle that had me pausing until oncoming traffic had passed before I could complete my turn! So yes... I can drive even the most challenging busses.

Spot the silly mistake! I welded the edges the wrong way around which means I have a little bit of a challenge coming up when it comes to attaching the bottom to the top! Fortunately I accept challenges and will spank this one soundly. The central bar is just there to hold the two parallel bars apart in order to make construction of the rest easier. It also allows me to take just the top under the bus in order to fit it properly. That means for marking where the holes for the bolt holes will go and drilling the holes in the underside of the ribs.

Ideally I’d have liked to have done the remains of my underbody wiring today but I think building my battery cage is probably going to take the whole day. (As the astute will realise, I’m blogging as I work). 

Eventually after taking until dusk, I managed to get most of the battery cage together. Remaining to do are several welds - the battery holder is just tacked on by a single weld at the moment. I’d been underneath and drilled mounting holes so the cage and battery will be suspended from (currently) eight 5/16 bolts. At a rough guess I’d say my holder weighs 10lbs though it could be about 5lbs. That means the whole caboodle weighs 30lbs. Even if it weighed 40lbs (which it doesn’t) then each bolt has to support 5lbs or 15lbs with a lot of downward force applied. I’d say that it’ll hold nicely.

That’s what it looked like at the time the daylight hopped on the train and escaped. The next stage is to complete the welds and to add a couple of tie-downs so the battery can be secured into its cage. I’ll also bolt my 30A resetting breaker to the cage so that the battery will be protected in the event of overload. I might add a non-resetting breaker or even just say stuff it and put a non-resetting breaker anyway.

I didn’t get the time to do any more wiring under the bus but if today had been twice as long then I might have had time. Too many coffee breaks and doughnuts slowed me down a bit. In fact I was asked today if I was a policeman - such is my love of pizza and doughnuts and coffee!