>>619970> However in the meantime, I am looking for a small lithium ion battery as a stopgap measure and to use> as a charger(while plugged in to the cigarette lighter and the car running) for my laptop.Don't waste your money.
The reason you van's starter battery is dying is because you're using it to power your laptop for hours on end, the van battery is _already fucked_ from you over-discharging it and it will only get shittier until it's completely dead.
The small lithium ion "jump pack" you want to get won't solve your problem, as you need a new starter battery anyways.
You need to stop using the van's starter battery for long term power, it's not made for that and you've already mortally wounded it by doing so.
Buy a battery power pack box (pic related) which is already wired up for your purposes and drop in an AGM battery (at 55-100Ah) and use that for your camping electrical needs, DO NOT use the van's starter battery for anything other then to start the van.
