Melted battery terminal!!!!

[dillond666]

Hi EV_dub,

When you say your controller overheats when driving slowly in a high gear, I think you're right to suggest that although the battery amps are low the controller amps will be high. Remember the motor turns amps into torque, and driving in a high gear requires more torque thus more amps.
I was reading an EV book and it suggested that the technique for driving an EV is slightly different from driving an ICE car. It suggests driving in the lowest possible gear as that will require the least torque and therefore amps. Using less amps reduces the IsquaredR losses (handy if your cables are a little small).
Remember too that AGM batteries don't take too kindly to the depth of discharge that your Trojans will take, so you might not want to go too small with them. I am using SEC battery red tops but as my car isn't quite on the road yet I'm afraid I can't comment on their longevity yet.

Derek

[EV_dub]

Remember too that AGM batteries don't take too kindly to the depth of discharge that your Trojans will take, so you might not want to go too small with them. I am using SEC battery red tops but as my car isn't quite on the road yet I'm afraid I can't comment on their longevity yet.

Yes that's a good point. However the trojans dont perform well on a deep discharge, drawing moderate current over 60%dod the voltage drop is quite a lot, so you can't really use allot of the trojans capacity safely.

SEC batteries, have never heard of these, what are the advantages with them?

What project are you working on at the moment?

Regards

Dave

[dillond666]

The red top batteries are just an AGM style that are reputed to withstand deep cycling (if one believes the manufacturer). I'm using 160aH x 13 for 156v nominal.
Google for SEC industrial battery and you can get the info on them. I paid circa £150 +vat per 12v battery.

My project is an old 1952 Wolseley 6/80. 9" warp / 1000A zilla conversion. Youtube for "Dereks electric car project" if you want a look. Video 7 shows it running. Hope to finish this Summer so better hurry! I'll be running a variant of Peters BMS.

Derek