B300s new cord not compatible with AC300

The AC300 is designed to work with the B300 battery, while the AC500 is compatible with the B300S battery. However, it is currently not recommended to connect the B300S battery to the AC300.

Correction: The B300S also requires a P090D to P150D cable to connect to the AC300.

Works great. I’ve been running mine since January with no issues.

  • B300 is ON SALE on Amazon current at $1800.

  • B300s is currently listed at $2300 + $108 for the cable.

  • $600 more for the B300s…pretty steep with out getting some of the benefits of the better battery.

  • So, do you all think it is definitely worth the extra money to get the B300s?

  • Also, will the B300s plug into the B300 with out the adapter cable? And, if I do get the extra battery, is it better to connect #2 battery into #2, or #2 directly into base? If I get the B300s, will it matter which way it is connected?

Thanks for any input.

Why is it not recommended? It is a better, newer battery. Say 5 years from now, will you all still be making the B300 and B300s?

Hopefully somebody will weigh in on my other question as to whether it is worth the extra $600 to get the NOT-recommended but better battery. But it would help if we new why it is not recommended.


As I mentioned in my previous reply, when the B300S is connected to the AC300, the charging and discharging power are limited by the host, and the heating function is also disabled. I certainly know that B300S is better, but all functions will work properly when the B300S is connected to the AC500.

Thanks for the reply. I understand the AC300 will limit some of the advantages of the B300s. But I am not clear how…or if it is really a limitation.

  1. If I want to charge the B300s battery directly (max 500w input) but while still connected to the AC300, with a 460w panel (the panel is connected directly to my current B300 with max 200w input), my system will benefit from the additional direct solar charge, correct? I mean, the direct charging of the B300s isn’t limited by the Ac300, right?
  2. If I remove the B300s battery to take with me for the day, leaving the B300 still tethered to the AC300, would I not benefit from the better B300s battery if I ever plan to use it as a Standalone, even if normally keep it connected to the AC300?
  3. Regarding the heating function, if I connect a panel DIRECTLY to the B300s, while the B300s is connected to the AC300, would it not activate the self heating feature? So, if the B300s is connected to the AC300, and the AC300 has panels…I get that it will not wake the heater up in the B300s. But, will the B300s heater wake up if it has PV directly input?
  • In other words, I know I will lose some of the benefit of the newer battery (heating maybe…yes…no?, current limited to 75a)…but I don’t understand how else it is limited?

Thanks for the additional clarification.