Jump box at grid?

[janton9736]

What are you guys doing for your jump box at grid? I've been relying on my nice on-board lithium starting battery, but twice I have forgotten to turn off the electrical switch (Doh!) because Ihave to keep it on to wirelessly download my video, which takes a long time. Fortunately, I have not yet had the experience of getting strapped in to go to grid and find I have a dead battery - but I don't want to chance it anymore.

A friend gave me a link for a pre-wired SMH SY50 connector to match the one already on the race car. Are you guys using one of the new jump start things like the one I am showing below? Should I buy a regular 12 volt automotive starting battery?

Thanks in advance. I hate being this clueless about pit equipment. - Jeff

[Lotus7]

jeezuz, $360 ???????

I use a $60 lawn tractor battery (manageable size and weight) with a handle and Anderson jump plug. More than enough to start the car.

[janton9736]

That's around something I was thinking as well, but I did not have the imagination to fabricate a holder that was easily portable for a battery, cables etc. I decided to go with this, probably a LiPo battery inside which I AM NOT ENTIRELY COMFORTABLE WITH but it is so much lighter to carry around. I used it to start the car about 90 minutes ago. Its cold here, when it started a whole bunch of oily smoke came out for a few minutes, but went away. Normal? Or a good sign the apex seals are worn?

jeezuz, $360 ???????

I use a $60 lawn tractor battery (manageable size and weight) with a handle and Anderson jump plug. More than enough to start the car.

[fletch]

So what has worked well for my water cooled Super Vee, is a “garden tractor” sized lead acid AGM battery, in a simple carrying box that we use for any jump starts in the paddock (or shop).
And a second, much smaller lithium (?) type battery, that drops into my crews backpack for starts on the grid.
both batteries were purchased at our local Farm & Fleet.
Fletch

[TimH]

The various minipacks are great as a grid tool for emergency use, but for repeated starts in the paddock they might or might not last out the day before needing a recharge. There's no cheap substitute of a good ol' heavy wet cell, preferably with a handle. Good for multiple cars all weekend long.

[bassracer]

I started using the smaller LiPo jump packs since 2019 - cannot beat how portable they are, and they output good V. Aside of being slightly naïve about any charging risks or dangers, what i DO NOT like is that it self cycles off after about 5s of V, meaning repeated cranking, or cold starts that die quickly require unplugging/plugging to reset the jump. I'm sure there is a way to mod this, but is probably there for good reason.

This year I switched to small lithium onboard - Braille suggested to never use a Wet or AGM battery to jump inline with an online lithium because your onboard V will immediately try to charge the jump battery creating the exact opposite effect you want. So I'm not totally sure what the winning solution is yet - other than having another $200+ LiPo4 jump battery. Actually, Braille wanted me to just have a bigger onboard and never need a jump.

[J Leonard]

There may be others out there, but the EarthX jump pack does not require a reset.

[M.Sauce]

Do not jump start a lithium Ion battery with a lead acid battery. You will ruin the lithium Ion battery.